Bio


Fan's research interests are in fundamental studies of nanophotonic structures, especially photonic crystals and meta-materials, and applications of these structures in energy and information technology applications

Academic Appointments


Administrative Appointments


  • Director, the Edward L. Ginzton Laboratory, Stanford University (2014 - 2021)

Honors & Awards


  • Member, National Academy of Engineering (2024)
  • R. W. Wood Prize, Optica (Formerly the Optical Society of America) (2022)
  • Simons Investigator in Physics, Simons Foundation (2021)
  • Vannevar Bush Faculty Fellowship, Department of Defense (2017)
  • Fellow, IEEE (2010)
  • Fellow, SPIE (2009)
  • Fellow, American Physical Society (2008)
  • Adolph Lomb Medal, Optical Society of America (2007)
  • Award for Initiatives in Research, National Academy of Sciences (2007)
  • Fellow, Optical Society of America (2007)
  • David and Lucile Packard Fellowship in Science and Engineering, David and Lucile Packard Foundation (2003)
  • Career Award, National Science Foundation (2002)

Boards, Advisory Committees, Professional Organizations


  • Scientific Advisory Board, Max Planck Institute for the Science of Light (2022 - Present)
  • Co-Founder, Skycool Systems (2016 - Present)
  • Co-Founder, Flexcompute (2016 - Present)
  • Associate Editor, Applied Physics Letters (2013 - 2019)

Professional Education


  • PhD, MIT, Physics (1997)

2024-25 Courses


Stanford Advisees


All Publications


  • RCWA4D: Electromagnetic solver for layered structures with incommensurate periodicities COMPUTER PHYSICS COMMUNICATIONS Lou, B., Fan, S. 2025; 306
  • Legume: A free implementation of the guided-mode expansion method for photonic crystal slabs COMPUTER PHYSICS COMMUNICATIONS Zanotti, S., Minkov, M., Nigro, D., Gerace, D., Fan, S., Andreani, L. 2024; 304
  • On-chip multi-degree-of-freedom control of two-dimensional materials. Nature Tang, H., Wang, Y., Ni, X., Watanabe, K., Taniguchi, T., Jarillo-Herrero, P., Fan, S., Mazur, E., Yacoby, A., Cao, Y. 2024

    Abstract

    Two-dimensional materials (2DM) and their heterostructures offer tunable electrical and optical properties, primarily modifiable through electrostatic gating and twisting. Although electrostatic gating is a well-established method for manipulating 2DM, achieving real-time control over interfacial properties remains challenging in exploring 2DM physics and advanced quantum device technology1-6. Current methods, often reliant on scanning microscopes, are limited in their scope of application, lacking the accessibility and scalability of electrostatic gating at the device level. Here we introduce an on-chip platform for 2DM with in situ adjustable interfacial properties, using a microelectromechanical system (MEMS). This platform comprises compact and cost-effective devices with the ability of precise voltage-controlled manipulation of 2DM, including approaching, twisting and pressurizing actions. We demonstrate this technology by creating synthetic topological singularities, such as merons, in the nonlinear optical susceptibility of twisted hexagonal boron nitride (h-BN)7-10. A key application of this technology is the development of integrated light sources with real-time and wide-range tunable polarization. Furthermore, we predict a quantum analogue that can generate entangled photon pairs with adjustable entanglement properties. Our work extends the abilities of existing technologies in manipulating low-dimensional quantum materials and paves the way for new hybrid two- and three-dimensional devices, with promising implications in condensed-matter physics, quantum optics and related fields.

    View details for DOI 10.1038/s41586-024-07826-x

    View details for PubMedID 39169189

    View details for PubMedCentralID 7717928

  • Unitary control of partially coherent waves. I. Absorption PHYSICAL REVIEW B Guo, C., Fan, S. 2024; 110 (3)
  • Strong Coupling and Single-Photon Nonlinearity in Free-Electron Quantum Optics ACS PHOTONICS Karnieli, A., Roques-Carmes, C., Rivera, N., Fan, S. 2024
  • Unitary control of partially coherent waves. II. Transmission or reflection PHYSICAL REVIEW B Guo, C., Fan, S. 2024; 110 (3)
  • Free-Space Beam Steering with Twisted Bilayer Photonic Crystal Slabs ACS PHOTONICS Lou, B., Tang, H., Du, F., Gao, G., Mazur, E., Fan, S. 2024
  • One-dimensional non-Hermitian band structures as Riemann surfaces PHYSICAL REVIEW A Wang, H., Fan, L., Fan, S. 2024; 110 (1)
  • Theory for Broadband Large-Area Purcell Enhancement ACS PHOTONICS Benzaouia, M., Fan, S. 2024; 11 (7): 2667-2672
  • Mode distribution impact on photonic crystal surface emitting laser performance APL PHOTONICS Gautam, C., Pan, M., Seth, S., Rotter, T. J., Zhou, M., Thompson, B. J., Gibson, R., Fan, S., Balakrishnan, G., Zhou, W. 2024; 9 (7)

    View details for DOI 10.1063/5.0199361

    View details for Web of Science ID 001281643300001

  • Topological winding guaranteed coherent orthogonal scattering PHYSICAL REVIEW A Guo, C., Fan, S. 2024; 109 (6)
  • Nanoscale optical nonreciprocity with nonlinear metasurfaces. Nature communications Tripathi, A., Ugwu, C. F., Asadchy, V. S., Faniayeu, I., Kravchenko, I., Fan, S., Kivshar, Y., Valentine, J., Kruk, S. S. 2024; 15 (1): 5077

    Abstract

    Optical nonreciprocity is manifested as a difference in the transmission of light for the opposite directions of excitation. Nonreciprocal optics is traditionally realized with relatively bulky components such as optical isolators based on the Faraday rotation, hindering the miniaturization and integration of optical systems. Here we demonstrate free-space nonreciprocal transmission through a metasurface comprised of a two-dimensional array of nanoresonators made of silicon hybridized with vanadium dioxide (VO2). This effect arises from the magneto-electric coupling between Mie modes supported by the resonator. Nonreciprocal response of the nanoresonators occurs without the need for external bias; instead, reciprocity is broken by the incident light triggering the VO2 phase transition for only one direction of incidence. Nonreciprocal transmission is broadband covering over 100 nm in the telecommunication range in the vicinity of λ = 1.5 µm. Each nanoresonator unit cell occupies only ~0.1 λ3 in volume, with the metasurface thickness measuring about half-a-micron. Our self-biased nanoresonators exhibit nonreciprocity down to very low levels of intensity on the order of 150 W/cm2 or a µW per nanoresonator. We estimate picosecond-scale transmission fall times and sub-microsecond scale transmission rise. Our demonstration brings low-power, broadband and bias-free optical nonreciprocity to the nanoscale.

    View details for DOI 10.1038/s41467-024-49436-1

    View details for PubMedID 38871743

    View details for PubMedCentralID PMC11176174

  • Mesoscopic non-Hermitian skin effect PHYSICAL REVIEW A Poddubny, A., Zhong, J., Fan, S. 2024; 109 (6)
  • Light bullet generation via stimulated Brillouin scattering APL PHOTONICS Huang, D., Guo, C., Fan, S. 2024; 9 (6)

    View details for DOI 10.1063/5.0201756

    View details for Web of Science ID 001253520900001

  • Time-modulated near-field radiative heat transfer. Proceedings of the National Academy of Sciences of the United States of America Yu, R., Fan, S. 2024; 121 (17): e2401514121

    Abstract

    Near-field radiative heat transfer has recently attracted increasing interests for its applications in energy technologies, such as thermophotovoltaics. Existing works, however, are restricted to time-independent systems. Here, we explore near-field radiative heat transfer between two bodies under time modulation by developing a rigorous fluctuational electrodynamics formalism. We demonstrate that time modulation can result in the enhancement, suppression, elimination, or reversal of radiative heat flow between the two bodies, and can be used to create a radiative thermal diode with an infinite contrast ratio, as well as a near-field radiative heat engine that pumps heat from the cold to the hot bodies. The formalism reveals a fundamental symmetry relation in the radiative heat transfer coefficients that underlies these effects. Our results indicate the significant capabilities of time modulation for managing nanoscale radiative heat flow.

    View details for DOI 10.1073/pnas.2401514121

    View details for PubMedID 38640346

  • Nonreciprocal thermal photonics NATURE PHOTONICS Yang, S., Liu, M., Zhao, C., Fan, S., Qiu, C. 2024
  • Nanophotonic Heat Exchanger for Enhanced Near-Field Radiative Heat Transfer. Nano letters Tsurimaki, Y., Benzaouia, M., Fan, S. 2024

    Abstract

    Increasing near-field radiative heat transfer between two bodies separated by a vacuum gap is crucial for enhancing the power density in radiative energy transport and conversion devices. However, the largest radiative heat transfer coefficient between two realistic materials at room temperature is limited to around 2000 W/(m2·K) for a gap of 100 nm. Here, analogous to conventional plate-fin heat exchangers based on convection, we introduce the concept of a nanophotonic heat exchanger, which enhances near-field radiative heat transfer using two bodies with interpenetrating gratings. Our calculations, based on rigorous fluctuational electrodynamics, show that the radiative heat transfer coefficient between the bodies separated by a 100 nm gap can significantly exceed 2000 W/(m2·K) by increasing the aspect ratios of the gratings. We develop a semianalytical heat transfer model that agrees well with the rigorous calculations for design optimization. Our work opens new opportunities for enhancing near-field radiative heat transfer between any materials.

    View details for DOI 10.1021/acs.nanolett.4c00506

    View details for PubMedID 38565218

  • Universal and Ultrafast Quantum Computation Based on Free-Electron-Polariton Blockade PRX QUANTUM Karnieli, A., Tsesses, S., Yu, R., Rivera, N., Arie, A., Kaminer, I., Fan, S. 2024; 5 (1)
  • Three-Dimensional Reconfigurable Optical Singularities in Bilayer Photonic Crystals. Physical review letters Ni, X., Liu, Y., Lou, B., Zhang, M., Hu, E. L., Fan, S., Mazur, E., Tang, H. 2024; 132 (7): 073804

    Abstract

    Metasurfaces and photonic crystals have revolutionized classical and quantum manipulation of light and opened the door to studying various optical singularities related to phases and polarization states. However, traditional nanophotonic devices lack reconfigurability, hindering the dynamic switching and optimization of optical singularities. This paper delves into the underexplored concept of tunable bilayer photonic crystals (BPhCs), which offer rich interlayer coupling effects. Utilizing silicon nitride-based BPhCs, we demonstrate tunable bidirectional and unidirectional polarization singularities, along with spatiotemporal phase singularities. Leveraging these tunable singularities, we achieve dynamic modulation of bound-state-in-continuum states, unidirectional guided resonances, and both longitudinal and transverse orbital angular momentum. Our work paves the way for multidimensional control over polarization and phase, inspiring new directions in ultrafast optics, optoelectronics, and quantum optics.

    View details for DOI 10.1103/PhysRevLett.132.073804

    View details for PubMedID 38427898

  • Optical Tellegen metamaterial with spontaneous magnetization. Nature communications Safaei Jazi, S., Faniayeu, I., Cichelero, R., Tzarouchis, D. C., Asgari, M. M., Dmitriev, A., Fan, S., Asadchy, V. 2024; 15 (1): 1293

    Abstract

    The nonreciprocal magnetoelectric effect, also known as the Tellegen effect, promises a number of groundbreaking phenomena connected to fundamental (e.g., electrodynamics of axion and relativistic matter) and applied physics (e.g., magnetless isolators). We propose a three-dimensional metamaterial with an isotropic and resonant Tellegen response in the visible frequency range. The metamaterial is formed by randomly oriented bi-material nanocylinders in a host medium. Each nanocylinder consists of a ferromagnet in a single-domain magnetic state and a high-permittivity dielectric operating near the magnetic Mie-type resonance. The proposed metamaterial requires no external magnetic bias and operates on the spontaneous magnetization of the nanocylinders. By leveraging the emerging magnetic Weyl semimetals, we further show how a giant bulk effective magnetoelectric effect can be achieved in a proposed metamaterial, exceeding that of natural materials by almost four orders of magnitude.

    View details for DOI 10.1038/s41467-024-45225-y

    View details for PubMedID 38346950

    View details for PubMedCentralID 5440727

  • Gauge-Flux-Induced Anti-Pt Phase Transitions for Extreme Control of Channel-Drop Tunneling LASER & PHOTONICS REVIEWS Qin, C., Wang, B., Fan, S., Lu, P. 2024
  • Photonic Topological Spin Pump in Synthetic Frequency Dimensions. Physical review letters Suh, J., Kim, G., Park, H., Fan, S., Park, N., Yu, S. 2024; 132 (3): 033803

    Abstract

    Reducing geometrical complexity while preserving desired wave properties is critical for proof-of-concept studies in wave physics, as evidenced by recent efforts to realize photonic synthetic dimensions, isospectrality, and hyperbolic lattices. Laughlin's topological pump, which elucidates quantum Hall states in cylindrical geometry with a radial magnetic field and a time-varying axial magnetic flux, is a prime example of these efforts. Here we propose a two-dimensional dynamical photonic system for the topological pumping of pseudospin modes by exploiting synthetic frequency dimensions. The system provides the independent control of pseudomagnetic fields and electromotive forces achieved by the interplay between mode-dependent and mode-independent gauge fields. To address the axial open boundaries and azimuthal periodicity of the system, we define the adjusted local Chern marker with rotating azimuthal coordinates, proving the nontrivial topology of the system. We demonstrate the adiabatic pumping for crosstalk-free frequency conversion with wave front molding. Our approach allows for reproducing Laughlin's thought experiment at room temperature with a scalable setup.

    View details for DOI 10.1103/PhysRevLett.132.033803

    View details for PubMedID 38307059

  • Radiative cooling textiles using industry-standard particle-free nonporous micro-structured fibers NANOPHOTONICS Catrysse, P. B., Fan, S. 2024
  • Unitary Control of Photonic Absorption and Emission Guo, C., Fan, S., Seletskiy, D. V., Kuno, M. K., Pauzauskie, P. J. SPIE-INT SOC OPTICAL ENGINEERING. 2024

    View details for DOI 10.1117/12.3004842

    View details for Web of Science ID 001211427500003

  • Photonic Spin Hopfions and Monopole Loops. Physical review letters Wang, H., Fan, S. 2023; 131 (26): 263801

    Abstract

    Spin textures with various topological orders are of great theoretical and practical interest. Hopfion, a spin texture characterized by a three-dimensional topological order was recently realized in electronic spin systems. Here, we show that monochromatic light can be structured such that its photonic spin exhibits a hopfion texture in the three-dimensional real space. We also provide ways to construct spin textures of arbitrary Hopf charges. When extending the system to four dimensions by introducing a parameter dimension, a new type of topological defect in the form of a monopole loop in photonic spin is encountered. Each point on the loop is a topological spin defect in three dimensions, and the loop itself carries quantized Hopf charges. Such photonic spin texture and defect may find application in control and sensing of nanoparticles, and optical generation of topological texture in motions of particles or fluids.

    View details for DOI 10.1103/PhysRevLett.131.263801

    View details for PubMedID 38215381

  • Spectral routers for snapshot multispectral imaging APPLIED PHYSICS LETTERS Catrysse, P. B., Fan, S. 2023; 123 (26)

    View details for DOI 10.1063/5.0176587

    View details for Web of Science ID 001134243900002

  • Angle-selective thermal emitter for directional radiative cooling and heating JOULE Zhou, J., Chen, T. G., Tsurimaki, Y., Hajj-Ahmad, A., Fan, L., Peng, Y., Xu, R., Wu, Y., Assawaworrarit, S., Fan, S., Cutkosky, M. R., Cui, Y. 2023; 7 (12)
  • Numerical and theoretical study of eigenenergy braids in two-dimensional photonic crystals PHYSICAL REVIEW B Zhong, J., Wojcik, C. C., Cheng, D., Fan, S. 2023; 108 (19)
  • Hyperbolic Polaritonic Rulers Based on van der Waals α-MoO3 Waveguides and Resonators. ACS nano Yu, S. J., Yao, H., Hu, G., Jiang, Y., Zheng, X., Fan, S., Heinz, T. F., Fan, J. A. 2023

    Abstract

    Low-dimensional, strongly anisotropic nanomaterials can support hyperbolic phonon polaritons, which feature strong light-matter interactions that can enhance their capabilities in sensing and metrology tasks. In this work, we report hyperbolic polaritonic rulers, based on microscale α-phase molybdenum trioxide (α-MoO3) waveguides and resonators suspended over an ultraflat gold substrate, which exhibit near-field polaritonic characteristics that are exceptionally sensitive to device geometry. Using scanning near-field optical microscopy, we show that these systems support strongly confined image polariton modes that exhibit ideal antisymmetric gap polariton dispersion, which is highly sensitive to air gap dimensions and can be described and predicted using a simple analytic model. Dielectric constants used for modeling are accurately extracted using near-field optical measurements of α-MoO3 waveguides in contact with the gold substrate. We also find that for nanoscale resonators supporting in-plane Fabry-Perot modes, the mode order strongly depends on the air gap dimension in a manner that enables a simple readout of the gap dimension with nanometer precision.

    View details for DOI 10.1021/acsnano.3c08735

    View details for PubMedID 37948673

  • Surface Phonon Polariton-Mediated Near-Field Radiative Heat Transfer at Cryogenic Temperatures. Physical review letters Yan, S., Luan, Y., Lim, J. W., Mittapally, R., Reihani, A., Wang, Z., Tsurimaki, Y., Fan, S., Reddy, P., Meyhofer, E. 2023; 131 (19): 196302

    Abstract

    Recent experiments, at room temperature, have shown that near-field radiative heat transfer (NFRHT) via surface phonon polaritons (SPhPs) exceeds the blackbody limit by several orders of magnitude. Yet, SPhP-mediated NFRHT at cryogenic temperatures remains experimentally unexplored. Here, we probe thermal transport in nanoscale gaps between a silica sphere and a planar silica surface from 77-300 K. These experiments reveal that cryogenic NFRHT has strong contributions from SPhPs and does not follow the T^{3} temperature (T) dependence of far-field thermal radiation. Our modeling based on fluctuational electrodynamics shows that the temperature dependence of NFRHT can be related to the confinement of heat transfer to two narrow frequency ranges and is well accounted for by a simple analytical model. These advances enable detailed NFRHT studies at cryogenic temperatures that are relevant to thermal management and solid-state cooling applications.

    View details for DOI 10.1103/PhysRevLett.131.196302

    View details for PubMedID 38000410

  • Asymmetric phase modulation of light with parity-symmetry broken metasurfaces OPTICA Mikheeva, E., Colom, R., Achouri, K., Overvig, A., Binkowski, F., Duboz, J., Cueff, S., Fan, S., Burger, S., Alu, A., Genevet, P. 2023; 10 (10): 1287-1294
  • Singular topology of scattering matrices PHYSICAL REVIEW B Guo, C., Li, J., Xiao, M., Fan, S. 2023; 108 (15)
  • Roadmap on spatiotemporal light fields JOURNAL OF OPTICS Shen, Y., Zhan, Q., Wright, L. G., Christodoulides, D. N., Wise, F. W., Willner, A. E., Zou, K., Zhao, Z., Porras, M. A., Chong, A., Wan, C., Bliokh, K. Y., Liao, C., Hernandez-Garcia, C., Murnane, M., Yessenov, M., Abouraddy, A. F., Wong, L., Go, M., Kumar, S., Guo, C., Fan, S., Papasimakis, N., Zheludev, N., Chen, L., Zhu, W., Agrawal, A., Mounaix, M., Fontaine, N. K., Carpenter, J., Jolly, S. W., Dorrer, C., Alonso, B., Lopez-Quintas, I., Lopez-Ripa, M., Sola, I. J., Huang, J., Zhang, H., Ruan, Z., Dorrah, A. H., Capasso, F., Forbes, A. 2023; 25 (9)
  • Colorful low-emissivity paints for space heating and cooling energy savings. Proceedings of the National Academy of Sciences of the United States of America Peng, Y., Lai, J. C., Xiao, X., Jin, W., Zhou, J., Yang, Y., Gao, X., Tang, J., Fan, L., Fan, S., Bao, Z., Cui, Y. 2023; 120 (34): e2300856120

    Abstract

    Space heating and cooling consume ~13% of global energy every year. The development of advanced materials that promote energy savings in heating and cooling is gaining increasing attention. To thermally isolate the space of concern and minimize the heat exchange with the outside environment has been recognized as one effective solution. To this end, here, we develop a universal category of colorful low-emissivity paints to form bilayer coatings consisting of an infrared (IR)-reflective bottom layer and an IR-transparent top layer in colors. The colorful visual appearance ensures the aesthetical effect comparable to conventional paints. High mid-infrared reflectance (up to ~80%) is achieved, which is more than 10 times as conventional paints in the same colors, efficiently reducing both heat gain and loss from/to the outside environment. The high near-IR reflectance also benefits reducing solar heat gain in hot days. The advantageous features of these paints strike a balance between energy savings and penalties for heating and cooling throughout the year, providing a comprehensive year-round energy-saving solution adaptable to a wide variety of climatic zones. Taking a typical midrise apartment building as an example, the application of our colorful low-emissivity paints can realize positive heating, ventilation, and air conditioning energy saving, up to 27.24 MJ/m2/y (corresponding to the 7.4% saving ratio). Moreover, the versatility of the paint, along with its applicability to diverse surfaces of various shapes and materials, makes the paints extensively useful in a range of scenarios, including building envelopes, transportation, and storage.

    View details for DOI 10.1073/pnas.2300856120

    View details for PubMedID 37579165

  • Experimental realization of convolution processing in photonic synthetic frequency dimensions. Science advances Fan, L., Wang, K., Wang, H., Dutt, A., Fan, S. 2023; 9 (32): eadi4956

    Abstract

    Convolution is an essential operation in signal and image processing and consumes most of the computing power in convolutional neural networks. Photonic convolution has the promise of addressing computational bottlenecks and outperforming electronic implementations. Performing photonic convolution in the synthetic frequency dimension, which harnesses the dynamics of light in the spectral degrees of freedom for photons, can lead to highly compact devices. Here, we experimentally realize convolution operations in the synthetic frequency dimension. Using a modulated ring resonator, we synthesize arbitrary convolution kernels using a predetermined modulation waveform with high accuracy. We demonstrate the convolution computation between input frequency combs and synthesized kernels. We also introduce the idea of an additive offset to broaden the kinds of kernels that can be implemented experimentally when the modulation strength is limited. Our work demonstrate the use of synthetic frequency dimension to efficiently encode data and implement computation tasks, leading to a compact and scalable photonic computation architecture.

    View details for DOI 10.1126/sciadv.adi4956

    View details for PubMedID 37566663

  • Direct observation of the violation of Kirchhoff's law of thermal radiation NATURE PHOTONICS Shayegan, K. J., Biswas, S., Zhao, B., Fan, S., Atwater, H. A. 2023
  • Experimental probe of twist angle-dependent band structure of on-chip optical bilayer photonic crystal. Science advances Tang, H., Lou, B., Du, F., Zhang, M., Ni, X., Xu, W., Jin, R., Fan, S., Mazur, E. 2023; 9 (28): eadh8498

    Abstract

    Recently, twisted bilayer photonic materials have been extensively used for creating and studying photonic tunability through interlayer couplings. While twisted bilayer photonic materials have been experimentally demonstrated in microwave regimes, a robust platform for experimentally measuring optical frequencies has been elusive. Here, we demonstrate the first on-chip optical twisted bilayer photonic crystal with twist angle-tunable dispersion and great simulation-experiment agreement. Our results reveal a highly tunable band structure of twisted bilayer photonic crystals due to moiré scattering. This work opens the door to realizing unconventional twisted bilayer properties and novel applications in optical frequency regimes.

    View details for DOI 10.1126/sciadv.adh8498

    View details for PubMedID 37436985

  • Tunable magnetless optical isolation with twisted Weyl semimetals NANOPHOTONICS Chistyakov, V. A., Asadchy, V. S., Fan, S., Alu, A., Krasnok, A. 2023
  • Exceptional points and non-Hermitian photonics at the nanoscale. Nature nanotechnology Li, A., Wei, H., Cotrufo, M., Chen, W., Mann, S., Ni, X., Xu, B., Chen, J., Wang, J., Fan, S., Qiu, C. W., Alù, A., Chen, L. 2023

    Abstract

    Exceptional points (EPs) arising in non-Hermitian systems have led to a variety of intriguing wave phenomena, and have been attracting increased interest in various physical platforms. In this Review, we highlight the latest fundamental advances in the context of EPs in various nanoscale systems, and overview the theoretical progress related to EPs, including higher-order EPs, bulk Fermi arcs and Weyl exceptional rings. We peek into EP-associated emerging technologies, in particular focusing on the influence of noise for sensing near EPs, improving the efficiency in asymmetric transmission based on EPs, optical isolators in nonlinear EP systems and novel concepts to implement EPs in topological photonics. We also discuss the constraints and limitations of the applications relying on EPs, and offer parting thoughts about promising ways to tackle them for advanced nanophotonic applications.

    View details for DOI 10.1038/s41565-023-01408-0

    View details for PubMedID 37386141

  • Multi-dimensional band structure spectroscopy in the synthetic frequency dimension. Light, science & applications Cheng, D., Lustig, E., Wang, K., Fan, S. 2023; 12 (1): 158

    Abstract

    The concept of synthetic dimensions in photonics provides a versatile platform in exploring multi-dimensional physics. Many of these physics are characterized by band structures in more than one dimensions. Existing efforts on band structure measurements in the photonic synthetic frequency dimension however are limited to either one-dimensional Brillouin zones or one-dimensional subsets of multi-dimensional Brillouin zones. Here we theoretically propose and experimentally demonstrate a method to fully measure multi-dimensional band structures in the synthetic frequency dimension. We use a single photonic resonator under dynamical modulation to create a multi-dimensional synthetic frequency lattice. We show that the band structure of such a lattice over the entire multi-dimensional Brillouin zone can be measured by introducing a gauge potential into the lattice Hamiltonian. Using this method, we perform experimental measurements of two-dimensional band structures of a Hermitian and a non-Hermitian Hamiltonian. The measurements reveal some of the general properties of point-gap topology of the non-Hermitian Hamiltonian in more than one dimensions. Our results demonstrate experimental capabilities to fully characterize high-dimensional physical phenomena in the photonic synthetic frequency dimension.

    View details for DOI 10.1038/s41377-023-01196-1

    View details for PubMedID 37369684

    View details for PubMedCentralID PMC10300075

  • Spectral phase singularity and topological behavior in perfect absorption PHYSICAL REVIEW B Liu, M., Chen, W., Hu, G., Fan, S., Christodoulides, D. N., Zhao, C., Qiu, C. 2023; 107 (24)
  • Microring-based programmable coherent optical neural networks. Optics express Wang, J., Rodrigues, S. P., Dede, E. M., Fan, S. 2023; 31 (12): 18871-18887

    Abstract

    Coherent programmable integrated photonics circuits have shown great potential as specialized hardware accelerators for deep learning tasks, which usually involve the use of linear matrix multiplication and nonlinear activation components. We design, simulate and train an optical neural network fully based on microring resonators, which shows advantages in terms of device footprint and energy efficiency. We use tunable coupled double ring structures as the interferometer components for the linear multiplication layers and modulated microring resonators as the reconfigurable nonlinear activation components. We then develop optimization algorithms to train the direct tuning parameters such as applied voltages based on the transfer matrix method and using automatic differentiation for all optical components.

    View details for DOI 10.1364/OE.492551

    View details for PubMedID 37381317

  • Jaynes-Cummings interaction between low-energy free electrons and cavity photons. Science advances Karnieli, A., Fan, S. 2023; 9 (22): eadh2425

    Abstract

    The Jaynes-Cummings Hamiltonian is at the core of cavity quantum electrodynamics; however, it relies on bound-electron emitters fundamentally limited by the binding Coulomb potential. In this work, we propose theoretically a new approach to realizing the Jaynes-Cummings model using low-energy free electrons coupled to dielectric microcavities and exemplify several quantum technologies made possible by this approach. Using quantum recoil, a large detuning inhibits the emission of multiple consecutive photons, effectively transforming the free electron into a few-level system coupled to the cavity mode. We show that this approach can be used for generation of single photons, photon pairs, and even a quantum SWAP gate between a photon and a free electron, with unity efficiency and high fidelity. Tunable by their kinetic energy, quantum free electrons are inherently versatile emitters with an engineerable emission wavelength. Hence, they pave the way toward new possibilities for quantum interconnects between photonic platforms at disparate spectral regimes.

    View details for DOI 10.1126/sciadv.adh2425

    View details for PubMedID 37256955

  • Inverse Design of Optical Switch Based on Bilevel Optimization Inspired by Meta-Learning ACS PHOTONICS Lou, B., Rodriguez, J., Wang, B., Cappelli, M., Fan, S. 2023
  • Detecting the relative phase between different frequency components of a photon using a three-level A atom coupled to a waveguide PHYSICAL REVIEW A Zhong, J., Rituraj, F., Dinc, F., Fan, S. 2023; 107 (5)
  • Experimental evaluation of digitally verifiable photonic computing for blockchain and cryptocurrency OPTICA Pai, S., Park, T., Ball, M., Penkovsky, B., Dubrovsky, M., Abebe, N., Milanizadeh, M., Morichetti, F., Melloni, A., Fan, S., Solgaard, O. 2023; 10 (5): 552-560
  • Universal embedding of a non-Hermitian reciprocal scattering optical system into a Hermitian time-reversal-invariant system PHYSICAL REVIEW A Minkov, M., Wang, H., Fan, S. 2023; 107 (5)
  • Closing the Collection on Photovoltaic Energy Conversion PHYSICAL REVIEW APPLIED Fan, S., Mi, Z. 2023; 19 (5)
  • Increasing the Q-Contrast in Large Photonic Crystal Slab Resonators Using Bound-States-in-Continuum ACS PHOTONICS Zhou, M., Kalapala, A., Pan, M., Gibson, R., Reilly, K., Rotter, T., Balakrishnan, G., Bedford, R., Zhou, W., Fan, S. 2023
  • Experimentally realized in situ backpropagation for deep learning in photonic neural networks. Science (New York, N.Y.) Pai, S., Sun, Z., Hughes, T. W., Park, T., Bartlett, B., Williamson, I. A., Minkov, M., Milanizadeh, M., Abebe, N., Morichetti, F., Melloni, A., Fan, S., Solgaard, O., Miller, D. A. 2023; 380 (6643): 398-404

    Abstract

    Integrated photonic neural networks provide a promising platform for energy-efficient, high-throughput machine learning with extensive scientific and commercial applications. Photonic neural networks efficiently transform optically encoded inputs using Mach-Zehnder interferometer mesh networks interleaved with nonlinearities. We experimentally trained a three-layer, four-port silicon photonic neural network with programmable phase shifters and optical power monitoring to solve classification tasks using "in situ backpropagation," a photonic analog of the most popular method to train conventional neural networks. We measured backpropagated gradients for phase-shifter voltages by interfering forward- and backward-propagating light and simulated in situ backpropagation for 64-port photonic neural networks trained on MNIST image recognition given errors. All experiments performed comparably to digital simulations ([Formula: see text]94% test accuracy), and energy scaling analysis indicated a route to scalable machine learning.

    View details for DOI 10.1126/science.ade8450

    View details for PubMedID 37104594

  • Majorization Theory for Unitary Control of Optical Absorption and Emission. Physical review letters Guo, C., Fan, S. 2023; 130 (14): 146202

    Abstract

    Unitary control changes the absorption and emission of an object by transforming the external light modes. It is widely used and underlies coherent perfect absorption. Yet two basic questions remain unanswered: For a given object under unitary control, what absorptivity α, emissivity e, and their contrast δ=e-α are attainable? How to obtain a given α, e, or δ? We answer both questions using the mathematics of majorization. We show that unitary control can achieve perfect violation or preservation of Kirchhoff's law in nonreciprocal objects, and uniform absorption or emission for any object.

    View details for DOI 10.1103/PhysRevLett.130.146202

    View details for PubMedID 37084437

  • Metasurface-based realization of photonic time crystals. Science advances Wang, X., Mirmoosa, M. S., Asadchy, V. S., Rockstuhl, C., Fan, S., Tretyakov, S. A. 2023; 9 (14): eadg7541

    Abstract

    Photonic time crystals are artificial materials whose electromagnetic properties are uniform in space but periodically vary in time. The synthesis of these materials and experimental observation of their physics remain very challenging because of the stringent requirement for uniform modulation of material properties in volumetric samples. In this work, we extend the concept of photonic time crystals to two-dimensional artificial structures-metasurfaces. We demonstrate that time-varying metasurfaces not only preserve key physical properties of volumetric photonic time crystals despite their simpler topology but also host common momentum bandgaps shared by both surface and free-space electromagnetic waves. On the basis of a microwave metasurface design, we experimentally confirmed the exponential wave amplification inside a momentum bandgap and the possibility to probe bandgap physics by external (free-space) excitations. The proposed metasurface serves as a straightforward material platform for realizing emerging photonic space-time crystals and as a realistic system for the amplification of surface-wave signals in future wireless communications.

    View details for DOI 10.1126/sciadv.adg7541

    View details for PubMedID 37018399

  • Observation of Negative Effective Thermal Diffusion in Gold Films ACS PHOTONICS Block, A., Yu, R., Un, I., Varghese, S., Liebel, M., van Hulst, N. F., Fan, S., Tielrooij, K., Sivan, Y. 2023; 10 (4): 1150-1158
  • Efficient biphoton emission in semiconductors by single-photon recycling PHYSICAL REVIEW A Rituraj, S., Fan, S., Yu, Z., Boieriu, P., Krishnamurthy, S. 2023; 107 (3)
  • Time reflection and refraction in synthetic frequency dimension PHYSICAL REVIEW RESEARCH Long, O. Y., Wang, K., Dutt, A., Fan, S. 2023; 5 (1)
  • Moving media as photonic heat engine and pump PHYSICAL REVIEW B Tsurimaki, Y., Yu, R., Fan, S. 2023; 107 (11)
  • Manipulating Coherence of Near-Field Thermal Radiation in Time-Modulated Systems. Physical review letters Yu, R., Fan, S. 2023; 130 (9): 096902

    Abstract

    We show that the spatial coherence of thermal radiation can be manipulated in time-modulated photonic systems supporting surface polaritons. We develop a fluctuational electrodynamics formalism for such systems to calculate the cross-spectral density tensor of the emitted thermal electromagnetic fields in the near-field regime. Our calculations indicate that, due to time-modulation, spatial coherence can be transferred between different frequencies, and correlations between different frequency components become possible. All these effects are unique to time-modulated systems. We also show that the decay rate of optical emitters can be controlled in the proximity of such time-modulated structure. Our findings open a promising avenue toward coherence control in thermal radiation, dynamical thermal imaging, manipulating energy transfer among thermal or optical emitters, efficient near-field radiative cooling, and engineering spontaneous emission rates of molecules.

    View details for DOI 10.1103/PhysRevLett.130.096902

    View details for PubMedID 36930900

  • Neural network learning with photonics and for photonic circuit design NANOPHOTONICS Brunner, D., Soriano, M. C., Fan, S. 2023
  • Artificial Non-Abelian Lattice Gauge Fields for Photons in the Synthetic Frequency Dimension. Physical review letters Cheng, D., Wang, K., Fan, S. 2023; 130 (8): 083601

    Abstract

    Non-Abelian gauge fields give rise to nontrivial topological physics. Here we develop a scheme to create an arbitrary SU(2) lattice gauge field for photons in the synthetic frequency dimension using an array of dynamically modulated ring resonators. The photon polarization is taken as the spin basis to implement the matrix-valued gauge fields. Using a non-Abelian generalization of the Harper-Hofstadter Hamiltonian as a specific example, we show that the measurement of the steady-state photon amplitudes inside the resonators can reveal the band structures of the Hamiltonian, which show signatures of the underlying non-Abelian gauge field. These results provide opportunities to explore novel topological phenomena associated with non-Abelian lattice gauge fields in photonic systems.

    View details for DOI 10.1103/PhysRevLett.130.083601

    View details for PubMedID 36898123

  • Thermally Responsive Hydrogels for Passive Temperature Regulation under Direct Sunlight ADVANCED PHOTONICS RESEARCH Xie, D., Li, W., Richards, C. A., Gao, H., Chen, C., Miljkovic, N., Fan, S., Lee, J., Joshi, S. N., Braun, P. V. 2023
  • Light control with Weyl semimetals ELIGHT Guo, C., Asadchy, V. S., Zhao, B., Fan, S. 2023; 3 (1)
  • Quantum sensing of strongly coupled light-matter systems using free electrons. Science advances Karnieli, A., Tsesses, S., Yu, R., Rivera, N., Zhao, Z., Arie, A., Fan, S., Kaminer, I. 2023; 9 (1): eadd2349

    Abstract

    Strong coupling in light-matter systems is a central concept in cavity quantum electrodynamics and is essential for many quantum technologies. Especially in the optical range, full control of highly connected multi-qubit systems necessitates quantum coherent probes with nanometric spatial resolution, which are currently inaccessible. Here, we propose the use of free electrons as high-resolution quantum sensors for strongly coupled light-matter systems. Shaping the free-electron wave packet enables the measurement of the quantum state of the entire hybrid systems. We specifically show how quantum interference of the free-electron wave packet gives rise to a quantum-enhanced sensing protocol for the position and dipole orientation of a subnanometer emitter inside a cavity. Our results showcase the great versatility and applicability of quantum interactions between free electrons and strongly coupled cavities, relying on the unique properties of free electrons as strongly interacting flying qubits with miniscule dimensions.

    View details for DOI 10.1126/sciadv.add2349

    View details for PubMedID 36598994

  • Power monitoring in a feedforward photonic network using two output detectors NANOPHOTONICS Pai, S., Valdez, C., Park, T., Milanizadeh, M., Morichetti, F., Melloni, A., Fan, S., Solgaard, O., Miller, D. B. 2023
  • Response to comment on "Does non-reciprocity break the Shockley-Queisser limit in single-junction solar cells?" [Appl. Phys. Lett. 122, 016101 (2023)] APPLIED PHYSICS LETTERS Park, Y., Fan, S. 2023; 122 (1)

    View details for DOI 10.1063/5.0134492

    View details for Web of Science ID 000908410500003

  • Frequency Response Characteristics of High-Power Photonic Crystal Surface-Emitting Lasers Pan, M., Gautam, C., Kalapala, A., Chen, Y., Rotter, T., Zhou, M., Gibson, R., Bedford, R., Fan, S., Balakrishnan, G., Zhou, W., IEEE IEEE. 2023
  • Unitary Control of Optical Absorption and Emission Guo, C., Fan, S., IEEE IEEE. 2023
  • Nonreciprocal Thermal Emission Using Spatiotemporal Modulation of Graphene ACS PHOTONICS Ghanekar, A., Wang, J., Guo, C., Fan, S., Povinelli, M. L. 2022
  • Floquet-Mie Theory for Time-Varying Dispersive Spheres LASER & PHOTONICS REVIEWS Ptitcyn, G., Lamprianidis, A., Karamanos, T., Asadchy, V., Alaee, R., Mueller, M., Albooyeh, M., Mirmoosa, M., Fan, S., Tretyakov, S., Rockstuhl, C. 2022
  • Topological spin defects of light OPTICA [Anonymous] 2022; 9 (12): 1417-1423
  • Tunable guided resonance in twisted bilayer photonic crystal. Science advances Lou, B., Wang, B., Rodríguez, J. A., Cappelli, M., Fan, S. 2022; 8 (48): eadd4339

    Abstract

    We experimentally demonstrate tunable guided resonance in twisted bilayer photonic crystals. Both the numerically and the experimentally obtained transmission spectra feature resonances with frequencies strongly dependent on the twist angle, as well as resonances with frequencies that are largely independent of the twist angle. These resonant features can be well understood with a simple analytic theory based on band folding. Our work illustrates the rich tunable resonance physics in twisted bilayer systems.

    View details for DOI 10.1126/sciadv.add4339

    View details for PubMedID 36449612

  • Thermal photonics with broken symmetries ELIGHT Liu, T., Guo, C., Li, W., Fan, S. 2022; 2 (1)
  • Nonreciprocal Thermophotovoltaic Systems ACS PHOTONICS Park, Y., Omair, Z., Fan, S. 2022
  • Super-Large-Scale Hierarchically Porous Films Based on Self-Assembled Eye-Like Air Pores for High-Performance Daytime Radiative Cooling. Small (Weinheim an der Bergstrasse, Germany) Tian, Q., Tu, X., Yang, L., Liu, H., Zhou, Y., Xing, Y., Chen, Z., Fan, S., Evans, J., He, S. 2022: e2205091

    Abstract

    Metal-free polymer daytime radiative cooling coatings with hierarchical eye-like air pores are proposed and fabricated with a super-large-scale film-stretching method. The hierarchically porous film (HPF) can be further coated with polymethyl methacrylate (PMMA) micro-hemispheres, forming coated HPF (cHPF), which do not dramatically change the optical or thermal properties. The cHPF is slightly better with a lower solar absorptivity (2.4%) and a higher thermal emissivity over the atmospheric transparency window (90.1%). The low solar absorptivity is due to the strong scattering of the hierarchical eye-like air pores, while the molecular vibrations and the focusing effect of the PMMA micro-hemispheres contribute to the high emissivity. An average mid-day temperature reduction of 7.92 °C is achieved relative to the air temperature, and the average cooling power reaches 116.0 W m-2 , which are much better than the cooling performances of the commercial cooling cushion. During the day, the cHPF-covered simulated building is up to 6.47 and 4.84 °C cooler than the ambient and the white painted counterpart, respectively. The film is durable and resistant to chemical etching, and very promising to use globally, especially in warm and tropical regions.

    View details for DOI 10.1002/smll.202205091

    View details for PubMedID 36328709

  • Nanophotonic detector array to enable direct thermal infrared vision. Optics express Khandekar, C., Jin, W., Fan, S. 2022; 30 (21): 39222-39233

    Abstract

    Detection of infrared (IR) photons in a room-temperature IR camera is carried out by a two-dimensional array of microbolometer pixels which exhibit temperature-sensitive resistivity. When IR light coming from the far-field is focused onto this array, microbolometer pixels are heated up in proportion to the temperatures of the far-field objects. The resulting resistivity change of each pixel is measured via on-chip electronic readout circuit followed by analog to digital (A/D) conversion, image processing, and presentation of the final IR image on a separate information display screen. In this work, we introduce a new nanophotonic detector as a minimalist alternative to microbolometer such that the final IR image can be presented without using the components required for A/D conversion, image processing and display. In our design, the detector array is illuminated with visible laser light and the reflected light itself carries the IR image which can be directly viewed. We numerically demonstrate this functionality using a resonant waveguide grating structure made of typical materials such as silicon carbide, silicon nitride, and silica for which lithography techniques are well-developed. We clarify the requirements to tackle the issues of fabrication nonuniformities and temperature drifts in the detector array. We envision a potential near-eye display device for direct IR vision based on timely use of diffractive optical waveguides in augmented reality headsets and tunable visible laser sources. Our work indicates a way to achieve thermal IR vision for suitable use cases with lower cost, smaller form factor, and reduced power consumption compared to the existing thermal IR cameras.

    View details for DOI 10.1364/OE.475296

    View details for PubMedID 36258467

  • Eigenvalue topology of non-Hermitian band structures in two and three dimensions PHYSICAL REVIEW B Wojcik, C. C., Wang, K., Dutt, A., Zhong, J., Fan, S. 2022; 106 (16)
  • Trajectory tracking through the control of non-equilibrium Casimir force JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Iizuka, H., Fan, S. 2022; 289
  • Multidimensional Convolution Operation with Synthetic Frequency Dimensions in Photonics PHYSICAL REVIEW APPLIED Fan, L., Zhao, Z., Wang, K., Dutt, A., Wang, J., Buddhiraju, S., Wojcik, C. C., Fan, S. 2022; 18 (3)
  • Laser Cooling Assisted Thermal Management of Lightsails ACS PHOTONICS Jin, W., Li, W., Khandekar, C., Orenstein, M., Fan, S. 2022
  • Does non-reciprocity break the Shockley-Queisser limit in single-junction solar cells? APPLIED PHYSICS LETTERS Park, Y., Fan, S. 2022; 121 (11)

    View details for DOI 10.1063/5.0118129

    View details for Web of Science ID 000859384700008

  • Radiative-cooling-based nighttime electricity generation with power density exceeding 100 mW/m2. iScience Omair, Z., Assawaworrarit, S., Fan, L., Jin, W., Fan, S. 2022; 25 (8): 104858

    Abstract

    The outer space (3 K) represents an important thermodynamic resource. It has been known for decades that at nighttime, a sky-facing thermal emitter radiating strongly within the atmospheric transparency window (8-13mum), can reach below the ambient temperature. In recent studies, thermoelectric generators were used to harness this temperature difference between the emitter and ambient to generate electricity. However, the demonstrated power density has been limited by parasitic thermal losses. Here we show that these parasitic losses can be reduced through thermal engineering. We present a simple model showing the optimum power density can be approached by controlling the relation between the emitter area and the thermal resistance of the thermoelectric generator. We show that the stacking of multiple thermoelectric generators is an effective way to approach this optimum. We experimentally demonstrate a generated electric power density >100 mW/m2, representing>2-fold improvement over the previous results for nighttime radiative cooling.

    View details for DOI 10.1016/j.isci.2022.104858

    View details for PubMedID 35996585

  • Doping-driven topological polaritons in graphene/alpha-MoO3 heterostructures. Nature nanotechnology Hu, H., Chen, N., Teng, H., Yu, R., Qu, Y., Sun, J., Xue, M., Hu, D., Wu, B., Li, C., Chen, J., Liu, M., Sun, Z., Liu, Y., Li, P., Fan, S., Garcia de Abajo, F. J., Dai, Q. 2022

    Abstract

    Control over charge carrier density provides an efficient way to trigger phase transitions and modulate the optoelectronic properties of materials. This approach can also be used to induce topological transitions in the optical response of photonic systems. Here we report a topological transition in the isofrequency dispersion contours of hybrid polaritons supported by a two-dimensional heterostructure consisting of graphene and alpha-phase molybdenum trioxide. By chemically changing the doping level of graphene, we observed that the topology of polariton isofrequency surfaces transforms from open to closed shapes as a result of doping-dependent polariton hybridization. Moreover, when the substrate was changed, the dispersion contour became dominated by flat profiles at the topological transition, thus supporting tunable diffractionless polariton propagation and providing local control over the optical contour topology. We achieved subwavelength focusing of polaritons down to 4.8% of the free-space light wavelength by using a 1.5-mum-wide silica substrate as an in-plane lens. Our findings could lead to on-chip applications in nanoimaging, optical sensing and manipulation of energy transfer at the nanoscale.

    View details for DOI 10.1038/s41565-022-01185-2

    View details for PubMedID 35982316

  • A tandem radiative/evaporative cooler for weather-insensitive and high-performance daytime passive cooling. Science advances Li, J., Wang, X., Liang, D., Xu, N., Zhu, B., Li, W., Yao, P., Jiang, Y., Min, X., Huang, Z., Zhu, S., Fan, S., Zhu, J. 2022; 8 (32): eabq0411

    Abstract

    Radiative cooling and evaporative cooling with low carbon footprint are regarded as promising passive cooling strategies. However, the intrinsic limits of continuous water supply with complex systems for evaporative cooling, and restricted cooling power as well as the strict requirement of weather conditions for radiative cooling, hinder the scale of their practical applications. Here, we propose a tandem passive cooler composed of bilayer polymer that enables dual-functional passive cooling of radiation and evaporation. Specifically, the high reflectivity to sunlight and mid-infrared emissivity of this polymer film allows excellent radiative cooling performance, and its good atmospheric water harvesting property of underlayer ensures self-supply of water and high evaporative cooling power. Consequently, this tandem passive cooler overcomes the fundamental difficulties of radiative cooling and evaporative cooling and shows the applicability under various conditions of weather/climate. It is expected that this design can expand the practical application domain of passive cooling.

    View details for DOI 10.1126/sciadv.abq0411

    View details for PubMedID 35960798

  • Scaling Challenges in High Power Photonic Crystal Surface-Emitting Lasers IEEE JOURNAL OF QUANTUM ELECTRONICS Kalapala, A., Song, A. Y., Pan, M., Gautam, C., Overman, L., Reilly, K., Rotter, T. J., Balakrishnan, G., Gibson, R., Bedford, R., Coleman, J. J., Fan, S., Zhou, W. 2022; 58 (4)
  • Effect of choices of boundary conditions on the numerical efficiency of direct solutions of finite difference frequency domain systems with perfectly matched layers OPTICS EXPRESS Zhao, N. Z., Fan, S. 2022; 30 (15): 26794-26806

    View details for DOI 10.1364/OE.457233

    View details for Web of Science ID 000828676200069

  • Mirror symmetric on-chip frequency circulation of light NATURE PHOTONICS Herrmann, J. F., Ansari, V., Wang, J., Witmer, J. D., Fan, S., Safavi-Naeini, A. H. 2022
  • Roadmap on topological photonics JOURNAL OF PHYSICS-PHOTONICS Price, H., Chong, Y., Khanikaev, A., Schomerus, H., Maczewsky, L. J., Kremer, M., Heinrich, M., Szameit, A., Zilberberg, O., Yang, Y., Zhang, B., Alu, A., Thomale, R., Carusotto, I., St-Jean, P., Amo, A., Dutt, A., Yuan, L., Fan, S., Yin, X., Peng, C., Ozawa, T., Blanco-Redondo, A. 2022; 4 (3)
  • Reciprocity Constraints on Reflection. Physical review letters Guo, C., Fan, S. 2022; 128 (25): 256101

    Abstract

    Reciprocity is a fundamental symmetry of Maxwell's equations. It is known that reciprocity imposes constraints on transmission, absorption, and emission. Here, we reveal reciprocity constraints on reflection. We determine the sets of all attainable reflection coefficients of n-port scattering matrices with prescribed singular values, both with and without assuming reciprocity. Their difference establishes reciprocity constraints and nonreciprocal behaviors. As an application, we examine the conditions for all-zero reflections. Our results deepen the understanding of reciprocity in optics.

    View details for DOI 10.1103/PhysRevLett.128.256101

    View details for PubMedID 35802447

  • Creating boundaries along a synthetic frequency dimension. Nature communications Dutt, A., Yuan, L., Yang, K. Y., Wang, K., Buddhiraju, S., Vuckovic, J., Fan, S. 2022; 13 (1): 3377

    Abstract

    Synthetic dimensions have garnered widespread interest for implementing high dimensional classical and quantum dynamics on low-dimensional geometries. Synthetic frequency dimensions, in particular, have been used to experimentally realize a plethora of bulk physics effects. However, in synthetic frequency dimension there has not been a demonstration of a boundary which is of paramount importance in topological physics due to the bulk-edge correspondence. Here we construct boundaries in the frequency dimension of dynamically modulated ring resonators by strongly coupling an auxiliary ring. We explore various effects associated with such boundaries, including confinement of the spectrum of light, discretization of the band structure, and the interaction of boundaries with one-way chiral modes in a quantum Hall ladder, which exhibits topologically robust spectral transport. Our demonstration of sharp boundaries fundamentally expands the capability of exploring topological physics, and has applications in classical and quantum information processing in synthetic frequency dimensions.

    View details for DOI 10.1038/s41467-022-31140-7

    View details for PubMedID 35697716

  • Temporal modulation brings metamaterials into new era. Light, science & applications Yuan, L., Fan, S. 2022; 11 (1): 173

    Abstract

    Temporal modulations in photonics bring many exotic optical phenomena in the time dimension while metamaterials provide powerful ways in manipulating light in the spatial domain. The authors envision the connection, Floquet Metamaterials, may deliver novel opportunities in nanophotonics.

    View details for DOI 10.1038/s41377-022-00870-0

    View details for PubMedID 35672282

  • Nonreciprocal infrared absorption via resonant magneto-optical coupling to InAs. Science advances Shayegan, K. J., Zhao, B., Kim, Y., Fan, S., Atwater, H. A. 2022; 8 (18): eabm4308

    Abstract

    Nonreciprocal elements are a vital building block of electrical and optical systems. In the infrared regime, there is a particular interest in structures that break reciprocity because their thermal absorptive (and emissive) properties should not obey the Kirchhoff thermal radiation law. In this work, we break time-reversal symmetry and reciprocity in n-type-doped magneto-optic InAs with a static magnetic field where light coupling is mediated by a guided-mode resonator structure, whose resonant frequency coincides with the epsilon-near-zero resonance of the doped indium arsenide. Using this structure, we observe the nonreciprocal absorptive behavior as a function of magnetic field and scattering angle in the infrared. Accounting for resonant and nonresonant optical scattering, we reliably model experimental results that break reciprocal absorption relations in the infrared. The ability to design these nonreciprocal absorbers opens an avenue to explore devices with unequal absorptivity and emissivity in specific channels.

    View details for DOI 10.1126/sciadv.abm4308

    View details for PubMedID 35522747

  • Truncation-dependent PT phase transition for the edge states of a two-dimensional non-Hermitian system PHYSICAL REVIEW B Cheng, D., Peng, B., Xiao, M., Chen, X., Yuan, L., Fan, S. 2022; 105 (20)
  • Adjoint Kirchhoff?s Law and General Symmetry Implications for All Thermal Emitters PHYSICAL REVIEW X Guo, C., Zhao, B., Fan, S. 2022; 12 (2)
  • Low-overhead distribution strategy for simulation and optimization of large-area metasurfaces NPJ COMPUTATIONAL MATERIALS Skarda, J., Trivedi, R., Su, L., Ahmad-Stein, D., Kwon, H., Han, S., Fan, S., Vuckovic, J. 2022; 8 (1)
  • Violation of Kirchhoff's Law of Thermal Radiation with Space-Time Modulated Grating ACS PHOTONICS Ghanekar, A., Wang, J., Fan, S., Povinelli, M. L. 2022; 9 (4): 1157-1164
  • Design of Compact Meta-Crystal Slab for General Optical Convolution ACS PHOTONICS Wang, H., Jin, W., Guo, C., Zhao, N., Rodrigues, S. P., Fan, S. 2022; 9 (4): 1358-1365
  • Few-particle scattering from localized quantum systems in spatially structured bosonic baths QUANTUM Trivedi, R., Fischer, K., Fan, S., Vuckovic, J. 2022; 6
  • Observation of Weyl exceptional rings in thermal diffusion. Proceedings of the National Academy of Sciences of the United States of America Xu, G., Li, W., Zhou, X., Li, H., Li, Y., Fan, S., Zhang, S., Christodoulides, D. N., Qiu, C. W. 2022; 119 (15): e2110018119

    Abstract

    SignificanceThermal diffusion is dissipative and strongly related to non-Hermitian physics. At the same time, non-Hermitian Weyl systems have spurred tremendous interest across photonics and acoustics. This correlation has been long ignored and hence shed little light upon the question of whether the Weyl exceptional ring (WER) in thermal diffusion could exist. Intuitively, thermal diffusion provides no real parameter dimensions, thus prohibiting a topological nature and WER. This work breaks this perception by imitating synthetic dimensions via two spatiotemporal advection pairs. The WER is achieved in thermal diffusive systems. Both surface-like and bulk states are demonstrated by coupling two WERs with opposite topological charges. These findings extend topological notions to diffusions and motivate investigation of non-Hermitian diffusive and dissipative control.

    View details for DOI 10.1073/pnas.2110018119

    View details for PubMedID 35377805

  • Nighttime electric power generation at a density of 50 mW/m(2) via radiative cooling of a photovoltaic cell APPLIED PHYSICS LETTERS Assawaworrarit, S., Omair, Z., Fan, S. 2022; 120 (14)

    View details for DOI 10.1063/5.0085205

    View details for Web of Science ID 000788794800002

  • Subwavelength Bayer RGB color routers with perfect optical efficiency NANOPHOTONICS Catrysse, P. B., Zhao, N., Jin, W., Fan, S. 2022
  • Tunable Frequency Filter Based on Twisted Bilayer Photonic Crystal Slabs ACS PHOTONICS Lou, B., Fan, S. 2022; 9 (3): 800-805
  • Spectral emissivity modeling in multi-resonant systems using coupled-mode theory OPTICS EXPRESS Audhkhasi, R., Zhao, B., Fan, S., Yu, Z., Povinelli, M. L. 2022; 30 (6): 9463-9472

    Abstract

    The ability to design multi-resonant thermal emitters is essential to the advancement of a wide variety of applications, including thermal management and sensing. These fields would greatly benefit from the development of more efficient tools for predicting the spectral response of coupled, multi-resonator systems. In this work, we propose a semi-analytical prediction tool based on coupled-mode theory. In our approach, a complex thermal emitter is fully described by a set of coupled-mode parameters, which can be straightforwardly calculated from simulations of unit cells containing single and double resonators. We demonstrate the accuracy of our method by predicting and optimizing spectral response in a coupled, multi-resonant system based on hBN ribbons. The approach described here can greatly reduce the computational overhead associated with spectral design tasks in coupled, multi-resonant systems.

    View details for DOI 10.1364/OE.453275

    View details for Web of Science ID 000768611900098

    View details for PubMedID 35299373

  • Topological Materials for Functional Optoelectronic Devices ADVANCED FUNCTIONAL MATERIALS Chorsi, H., Cheng, B., Zhao, B., Toudert, J., Asadchy, V., Shoron, O. F., Fan, S., Matsunaga, R. 2022
  • Topological dissipation in a time-multiplexed photonic resonator network NATURE PHYSICS Leefmans, C., Dutt, A., Williams, J., Yuan, L., Porto, M., Nori, F., Fan, S., Marandi, A. 2022
  • Efficient method for accelerating line searches in adjoint optimization of photonic devices by combining Schur complement domain decomposition and Born series expansions OPTICS EXPRESS Zhao, N. Z., Boutami, S., Fan, S. 2022; 30 (4): 6413-6424

    Abstract

    A line search in a gradient-based optimization algorithm solves the problem of determining the optimal learning rate for a given gradient or search direction in a single iteration. For most problems, this is determined by evaluating different candidate learning rates to find the optimum, which can be expensive. Recent work has provided an efficient way to perform a line search with the use of the Shanks transformation of a Born series derived from the Lippman-Schwinger formalism. In this paper we show that the cost for performing such a line search can be further reduced with the use of the method of the Schur complement domain decomposition, which can lead to a 10-fold total speed-up resulting from the reduced number of iterations to convergence and reduced wall-clock time per iteration.

    View details for DOI 10.1364/OE.451718

    View details for Web of Science ID 000754931700138

    View details for PubMedID 35209580

  • Lineshape study of optical force spectra on resonant structures OPTICS EXPRESS Fan, L., Zhao, Z., Rituraj, Jin, W., Orenstein, M., Fan, S. 2022; 30 (4): 6142-6160

    Abstract

    Understanding the frequency spectrum of the optical force is important for controlling and manipulating micro- and nano-scale objects using light. Spectral resonances of these objects can significantly influence the optical force spectrum. In this paper, we develop a theoretical formalism based on the temporal coupled-mode theory that analytically describes the lineshapes of force spectra and their dependencies on resonant scatterers for arbitrary incident wavefronts. We obtain closed-form formulae and discuss the conditions for achieving symmetric as well as asymmetric lineshapes, pertaining, respectively, to a Lorentzian and Fano resonance. The relevance of formalism as a design tool is exemplified for a conceptual scheme of the size-sorting mechanism of small particles, which plays a role in biomedical diagnosis.

    View details for DOI 10.1364/OE.452764

    View details for Web of Science ID 000754931700117

    View details for PubMedID 35209557

  • Internal transformations and internal symmetries in linear photonic systems PHYSICAL REVIEW A Guo, C., Zhao, Z., Fan, S. 2022; 105 (2)
  • Polarization-Independent Isotropic Nonlocal Metasurfaces with Wavelength-Controlled Functionality PHYSICAL REVIEW APPLIED Long, O. Y., Guo, C., Jin, W., Fan, S. 2022; 17 (2)
  • Photonics and thermodynamics concepts in radiative cooling NATURE PHOTONICS Fan, S., Li, W. 2022
  • Concentrated radiative cooling and its constraint from reciprocity OPTICS EXPRESS Dong, M., Zhu, L., Jiang, B., Fan, S., Chen, Z. 2022; 30 (1): 275-285

    View details for DOI 10.1364/OE.445544

    View details for Web of Science ID 000738278500024

  • Protecting ice from melting under sunlight via radiative cooling. Science advances Li, J., Liang, Y., Li, W., Xu, N., Zhu, B., Wu, Z., Wang, X., Fan, S., Wang, M., Zhu, J. 2022; 8 (6): eabj9756

    Abstract

    As ice plays a critical role in various aspects of life, from food preservation to ice sports and ecosystem, it is desirable to protect ice from melting, especially under sunlight. The fundamental reason for ice melt under sunlight is related to the imbalanced energy flows of the incoming sunlight and outgoing thermal radiation. Therefore, radiative cooling, which can balance the energy flows without energy consumption, offers a sustainable approach for ice protection. Here, we demonstrate that a hierarchically designed radiative cooling film based on abundant and eco-friendly cellulose acetate molecules versatilely provides effective and passive protection to various forms/scales of ice under sunlight. This work provides inspiration for developing an effective, scalable, and sustainable route for preserving ice and other critical elements of ecosystems.

    View details for DOI 10.1126/sciadv.abj9756

    View details for PubMedID 35148187

  • Prospects and applications of photonic neural networks ADVANCES IN PHYSICS-X Huang, C., Sorger, V. J., Miscuglio, M., Al-Qadasi, M., Mukherjee, A., Lampe, L., Nichols, M., Tait, A. N., Ferreira de Lima, T., Marquez, B. A., Wang, J., Chrostowski, L., Fok, M. P., Brunner, D., Fan, S., Shekhar, S., Prucnal, P. R., Shastri, B. J. 2022; 7 (1)
  • Flashing light with nanophotonics. Science (New York, N.Y.) Yu, R., Fan, S. 2022; 375 (6583): 822-823

    Abstract

    Manipulation and enhancement of scintillation is achieved in nanophotonic structures.

    View details for DOI 10.1126/science.abn8478

    View details for PubMedID 35201880

  • Universal Behavior of the Scattering Matrix Near Thresholds in Photonics. Physical review letters Wojcik, C. C., Wang, H., Orenstein, M., Fan, S. 1800; 127 (27): 277401

    Abstract

    Scattering thresholds and their associated spectral square root branch points are ubiquitous in photonics. In this Letter, we show that the scattering matrix has a simple universal behavior near scattering thresholds. We use unitarity, reciprocity, and time-reversal symmetry to construct a two-parameter model for a two-port scattering matrix near a threshold. We demonstrate this universal behavior in three different optical systems, namely, a photonic crystal slab, a planar dielectric interface, and a junction between metallic waveguides of different widths.

    View details for DOI 10.1103/PhysRevLett.127.277401

    View details for PubMedID 35061418

  • Thermodynamics of Light Management in Near-Field Thermophotovoltaics PHYSICAL REVIEW APPLIED Papadakis, G. T., Orenstein, M., Yablonovitch, E., Fan, S. 2021; 16 (6)
  • Nonequilibrium lateral force and torque by thermally excited nonreciprocal surface electromagnetic waves PHYSICAL REVIEW B Khandekar, C., Buddhiraju, S., Wilkinson, P. R., Gimzewski, J. K., Rodriguez, A. W., Chase, C., Fan, S. 2021; 104 (24)
  • Coloured low-emissivity films for building envelopes for year-round energy savings NATURE SUSTAINABILITY Peng, Y., Fan, L., Jin, W., Ye, Y., Huang, Z., Zhai, S., Luo, X., Ma, Y., Tang, J., Zhou, J., Greenburg, L. C., Majumdar, A., Fan, S., Cui, Y. 2021
  • Reaching the Ultimate Efficiency of Solar Energy Harvesting with a Nonreciprocal Multijunction Solar Cell. Nano letters Park, Y., Zhao, B., Fan, S. 1800

    Abstract

    The Landsberg limit represents the ultimate efficiency limit of solar energy harvesting. Reaching this limit requires the use of nonreciprocal elements. The existing device configurations for attaining the Landsberg limit, however, are very complicated. Here, we introduce the concept of a nonreciprocal multijunction solar cell and show that such a cell can reach the Landsberg limit in the idealized situation where an infinite number of layers are used. We also show that such a nonreciprocal multijunction cell outperforms a standard reciprocal multijunction cell for a finite number of layers. Our work significantly simplifies the device configuration required to reach the ultimate limit of solar energy conversion and points to a pathway toward using nonreciprocity to improve solar energy harvesting.

    View details for DOI 10.1021/acs.nanolett.1c04288

    View details for PubMedID 34939814

  • Deterministic photonic quantum computation in a synthetic time dimension OPTICA Bartlett, B., Dutt, A., Fan, S. 2021; 8 (12): 1515-1523
  • Nonreciprocal Thermal Emitters Using Metasurfaces with Multiple Diffraction Channels PHYSICAL REVIEW APPLIED Zhao, B., Wang, J., Zhao, Z., Guo, C., Yu, Z., Fan, S. 2021; 16 (6)
  • Shockley-Queisser analysis of the temperature-efficiency correlation of solar cells in the presence of non- radiative heat transfer (vol 29, pg 27554, 2021) OPTICS EXPRESS Zhang, Z., Chen, K., Fan, S., Chen, Z. 2021; 29 (24): 39173

    Abstract

    This erratum corrects a typographical error in Fig. 2 of our published paper [Opt. Express29, 27554 (2021)10.1364/OE.434751].

    View details for DOI 10.1364/OE.440880

    View details for Web of Science ID 000722251200020

    View details for PubMedID 34809286

  • Phonon-induced anomalous gauge potential for photonic isolation in frequency space OPTICA Yang, J., Yuan, L., Qin, T., Zhang, F., Chen, Y., Jiang, X., Chen, X., Fan, S., Wan, W. 2021; 8 (11): 1448-1457
  • A perspective on the pathway towardfull wave simulation of large area metalenses (vol 119, 150502, 2021)<br> APPLIED PHYSICS LETTERS Hughes, T. W., Minkov, M., Liu, V., Yu, Z., Fan, S. 2021; 119 (20)

    View details for DOI 10.1063/5.0076487

    View details for Web of Science ID 000719676400005

  • Subambient daytime radiative cooling textile based on nanoprocessed silk NATURE NANOTECHNOLOGY Zhu, B., Li, W., Zhang, Q., Li, D., Liu, X., Wang, Y., Xu, N., Wu, Z., Li, J., Li, X., Catrysse, P. B., Xu, W., Fan, S., Zhu, J. 2021

    Abstract

    Decreasing energy consumption is critical to sustainable development. Because temperature regulation for human comfort consumes vast amounts of energy, substantial research efforts are currently directed towards developing passive personal thermal management techniques that cool the human body without any energy consumption1-9. Although various cooling textile designs have been proposed previously, textile-based daytime radiative cooling to a temperature below ambient has not been realized6-13. Silk, a natural protein fabric produced by moth caterpillars, is famous for its shimmering appearance and its cooling and comforting sensation on skin14-17. It has been recently recognized that silk, with its optical properties derived from its hierarchical microstructure, may represent a promising starting point for exploring daytime radiative cooling18-21. However, the intrinsic absorption of protein in the ultraviolet region prevents natural silk from achieving net cooling under sunlight. Here we explore the nanoprocessing of silk through a molecular bonding design and scalable coupling reagent-assisted dip-coating method, and demonstrate that nanoprocessed silk can achieve subambient daytime radiative cooling. Under direct sunlight (peak solar irradiance >900 W m-2) we observed a temperature of ~3.5 °C below ambient (for an ambient temperature of ~35 °C) for stand-alone nanoprocessed silks. We also observed a temperature reduction of 8 °C for a simulated skin when coated with nanoprocessed silk, compared with natural silk. This subambient daytime radiative cooling of nanoprocessed silk was achieved without compromising its wearability and comfort. This strategy of tailoring natural fabrics through scalable nanoprocessing techniques opens up new pathways to realizing thermoregulatory materials and provides an innovative way to sustainable energy.

    View details for DOI 10.1038/s41565-021-00987-0

    View details for Web of Science ID 000715703700003

    View details for PubMedID 34750560

  • Long-Range Directional Routing and Spatial Selection of High-Spin-Purity Valley Trion Emission in Monolayer WS2. ACS nano Chen, P., Li, Z., Qi, Y., Lo, T. W., Wang, S., Jin, W., Wong, K., Fan, S., Zayats, A. V., Lei, D. 2021

    Abstract

    Valley-dependent excitation and emission in transition metal dichalcogenides (TMDCs) have recently emerged as a new avenue for optical data manipulation, quantum optical technologies, and chiral photonics. The valley-polarized electronic states can be optically addressed through photonic spin-orbit interaction of excitonic emission, typically with plasmonic nanostructures, but their performance is limited by the low quantum yield of neutral excitons in TMDC multilayers and the large Ohmic loss of plasmonic systems. Here, we demonstrate a valleytronic system based on the trion emission in high-quantum-yield WS2 monolayers chirally coupled to a low-loss microfiber. The integrated system uses the spin properties of the waveguided modes to achieve long-range directional routing of valley excitations and also provides an approach to selectively address valley-dependent emission from different spatial locations around the microfiber. This valleytronic interface can be integrated with fiber communication devices, allowing for merging valley polarization and chiral photonics as an alternative mechanism for optical information transport and manipulation in classical and quantum regimes.

    View details for DOI 10.1021/acsnano.1c06955

    View details for PubMedID 34730338

  • Adaptive four-level modeling of laser cooling of solids APPLIED PHYSICS LETTERS Jin, W., Guo, C., Orenstein, M., Fan, S. 2021; 119 (18)

    View details for DOI 10.1063/5.0070422

    View details for Web of Science ID 000716756400006

  • Integrated cooling (i-Cool) textile of heat conduction and sweat transportation for personal perspiration management. Nature communications Peng, Y., Li, W., Liu, B., Jin, W., Schaadt, J., Tang, J., Zhou, G., Wang, G., Zhou, J., Zhang, C., Zhu, Y., Huang, W., Wu, T., Goodson, K. E., Dames, C., Prasher, R., Fan, S., Cui, Y. 2021; 12 (1): 6122

    Abstract

    Perspiration evaporation plays an indispensable role in human body heat dissipation. However, conventional textiles tend to focus on sweat removal and pay little attention to the basic thermoregulation function of sweat, showing limited evaporation ability and cooling efficiency in moderate/profuse perspiration scenarios. Here, we propose an integrated cooling (i-Cool) textile with unique functional structure design for personal perspiration management. By integrating heat conductive pathways and water transport channels decently, i-Cool exhibits enhanced evaporation ability and high sweat evaporative cooling efficiency, not merely liquid sweat wicking function. In the steady-state evaporation test, compared to cotton, up to over 100% reduction in water mass gain ratio, and 3 times higher skin power density increment for every unit of sweat evaporation are demonstrated. Besides, i-Cool shows about 3°C cooling effect with greatly reduced sweat consumption than cotton in the artificial sweating skin test. The practical application feasibility of i-Cool design principles is well validated based on commercial fabrics. Owing to its exceptional personal perspiration management performance, we expect the i-Cool concept can provide promising design guidelines for next-generation perspiration management textiles.

    View details for DOI 10.1038/s41467-021-26384-8

    View details for PubMedID 34675199

  • Space-Time Metasurfaces for Power Combining of Waves ACS PHOTONICS Wang, X., Asadchy, V. S., Fan, S., Tretyakov, S. A. 2021; 8 (10): 3034-3041
  • Editorial: Introducing the Collection on Photovoltaic Energy Conversion PHYSICAL REVIEW APPLIED Fan, S., Mi, Z. 2021; 16 (4)
  • Electron Pulse Compression with Optical Beat Note. Physical review letters Zhao, Z., Leedle, K. J., Black, D. S., Solgaard, O., Byer, R. L., Fan, S. 2021; 127 (16): 164802

    Abstract

    Compressing electron pulses is important in many applications of electron beam systems. In this study, we propose to use optical beat notes to compress electron pulses. The beat frequency is chosen to match the initial electron pulse duration, which enables the compression of electron pulses with a wide range of durations. This functionality extends the optical control of electron beams, which is important in compact electron beam systems such as dielectric laser accelerators. We also find that the dominant frequency of the electron charge density changes continuously along its drift trajectory, which may open up new opportunities in coherent interaction between free electrons and quantum or classical systems.

    View details for DOI 10.1103/PhysRevLett.127.164802

    View details for PubMedID 34723609

  • Electron Pulse Compression with Optical Beat Note PHYSICAL REVIEW LETTERS Zhao, Z., Leedle, K. J., Black, D. S., Solgaard, O., Byer, R. L., Fan, S. 2021; 127 (16)
  • A perspective on the pathway toward full wave simulation of large area metalenses APPLIED PHYSICS LETTERS Hughes, T. W., Minkov, M., Liu, V., Yu, Z., Fan, S. 2021; 119 (15)

    View details for DOI 10.1063/5.0071245

    View details for Web of Science ID 000754619000014

  • Nontrivial point-gap topology and non-Hermitian skin effect in photonic crystals PHYSICAL REVIEW B Zhong, J., Wang, K., Park, Y., Asadchy, V., Wojcik, C. C., Dutt, A., Fan, S. 2021; 104 (12)
  • Configurable Phase Transitions in a Topological Thermal Material. Physical review letters Xu, G., Li, Y., Li, W., Fan, S., Qiu, C. 2021; 127 (10): 105901

    Abstract

    Diffusive nature of thermal transportation fundamentally restricts topological characteristics due to the absence of a sufficient parametric space with complex dimensionalities. Here, we create an orthogonal advection space with two advective pairs to reveal the unexplored topological transitions in thermal material. We demonstrate four types of configurable thermal phases, including the nontrivial dynamic-equilibrium distribution, nonchiral steplike pi-phase transition, and another two trivial profiles related to the anti-parity-time symmetry nature. Our findings provide a recipe for realizing a topologically robust thermal system under arbitrary perturbations.

    View details for DOI 10.1103/PhysRevLett.127.105901

    View details for PubMedID 34533332

  • Violating Kirchhoff's Law of Thermal Radiation in Semitransparent Structures ACS PHOTONICS Park, Y., Asadchy, V. S., Zhao, B., Guo, C., Wang, J., Fan, S. 2021; 8 (8): 2417-2424
  • Inverse Design of Metasurfaces Based on Coupled-Mode Theory and Adjoint Optimization ACS PHOTONICS Zhou, M., Liu, D., Belling, S. W., Cheng, H., Kats, M. A., Fan, S., Povinelli, M. L., Yu, Z. 2021; 8 (8): 2265-2273
  • Generation of guided space-time wave packets using multilevel indirect photonic transitions in integrated photonics PHYSICAL REVIEW RESEARCH Guo, C., Fan, S. 2021; 3 (3)
  • Shockley-Queisser analysis of the temperature-efficiency correlation of solar cells in the presence of non-radiative heat transfer OPTICS EXPRESS Zhang, Z., Chen, K., Fan, S., Chen, Z. 2021; 29 (17): 27554-27561

    View details for DOI 10.1364/OE.434751

    View details for Web of Science ID 000683895800103

  • High-performance photonic transformers for DC voltage conversion. Nature communications Zhao, B., Assawaworrarit, S., Santhanam, P., Orenstein, M., Fan, S. 2021; 12 (1): 4684

    Abstract

    Direct current (DC) converters play an essential role in electronic circuits. Conventional high-efficiency DC voltage converters, especially step-up type, rely on switching operation, where energy is periodically stored within and released from inductors and/or capacitors connected in a variety of circuit topologies. Since these energy storage components, especially inductors, are fundamentally difficult to scale down, miniaturization of switching converters proves challenging. Furthermore, the resulting switching currents produce significant electromagnetic noise. To overcome the limitations of switching converters, photonic transformers, where voltage conversion is achieved through light emission and detection processes, have been demonstrated. However, the demonstrated efficiency is significantly below that of the switching converter. Here we perform a detailed balance analysis and show that with a monolithically integrated design that enables efficient photon transport, the photonic transformer can operate with a near-unity conversion efficiency and high voltage conversion ratio. We validate the theory with a transformer constructed with off-the-shelf discrete components. Our experiment showcases near noiseless operation and a voltage conversion ratio that is significantly higher than obtained in previous photonic transformers. Our findings point to the possibility of a high-performance optical solution to miniaturizing DC power converters and improving the electromagnetic compatibility and quality of electrical power.

    View details for DOI 10.1038/s41467-021-24955-3

    View details for PubMedID 34344884

  • Structured 3D linear space-time light bullets by nonlocal nanophotonics. Light, science & applications Guo, C., Xiao, M., Orenstein, M., Fan, S. 2021; 10 (1): 160

    Abstract

    We propose the generation of 3D linear light bullets propagating in free space using a single passive nonlocal optical surface. The nonlocal nanophotonics can generate space-time coupling without any need for bulky pulse-shaping and spatial modulation techniques. Our approach provides simultaneous control of various properties of the light bullets, including the external properties such as the group velocity and the propagation distance, and internal degrees of freedom such as the spin angular momentum and the orbital angular momentum.

    View details for DOI 10.1038/s41377-021-00595-6

    View details for PubMedID 34341327

  • Engineering arbitrarily oriented spatiotemporal optical vortices using transmission nodal lines OPTICA Wang, H., Guo, C., Jin, W., Song, A. Y., Fan, S. 2021; 8 (7): 966-971
  • Controllable finite ultra-narrow quality-factor peak in a perturbed Dirac-cone band structure of a photonic-crystal slab APPLIED PHYSICS LETTERS Song, A. Y., Kalapala, A., Gibson, R., Reilly, K., Rotter, T., Addamane, S., Wang, H., Guo, C., Balakrishnan, G., Bedford, R., Zhou, W., Fan, S. 2021; 119 (3)

    View details for DOI 10.1063/5.0056243

    View details for Web of Science ID 000674420200020

  • Arbitrary synthetic dimensions via multiboson dynamics on a one-dimensional lattice PHYSICAL REVIEW RESEARCH Cheng, D., Peng, B., Wang, D., Chen, X., Yuan, L., Fan, S. 2021; 3 (3)
  • Inverse Design of Plasma Metamaterial Devices for Optical Computing PHYSICAL REVIEW APPLIED Rodriguez, J. A., Abdalla, A. I., Wang, B., Lou, B., Fan, S., Cappelli, M. A. 2021; 16 (1)
  • Optimal two-photon excitation of bound states in non-Markovian waveguide QED PHYSICAL REVIEW A Trivedi, R., Malz, D., Sun, S., Fan, S., Vuckovic, J. 2021; 104 (1)
  • Isotropic topological second-order spatial differentiator operating in transmission mode OPTICS LETTERS Long, O. Y., Guo, C., Wang, H., Fan, S. 2021; 46 (13): 3247-3250

    Abstract

    Differentiation has widespread applications, particularly in image processing for edge detection. Significant advances have been made in using nanophotonic structures and metamaterials to perform such operations. In particular, a recent work demonstrated a topological differentiator in which the transfer function exhibited a topological charge, making the differentiation operation robust to variations in operating conditions. The demonstrated topological differentiator, however, operates in reflection mode at off-normal incidence and is difficult to integrate into compact imaging systems. In this work, we design a topological differentiator that operates isotropically in transmission mode at normal incidence. The device exhibits an optical transfer function with a symmetry-protected topological charge of ±2 and performs second-order differentiation. Our work points to the potential of harnessing topological concepts for optical computing applications.

    View details for DOI 10.1364/OL.430699

    View details for Web of Science ID 000668963500063

    View details for PubMedID 34197427

  • Synthetic frequency dimensions in dynamically modulated ring resonators APL PHOTONICS Yuan, L., Dutt, A., Fan, S. 2021; 6 (7)

    View details for DOI 10.1063/5.0056359

    View details for Web of Science ID 000691879600002

  • Single Gyrotropic Particle as a Heat Engine ACS PHOTONICS Guo, Y., Fan, S. 2021; 8 (6): 1623-1629
  • Quantum Entanglement and Modulation Enhancement of Free-Electron-Bound-Electron Interaction PHYSICAL REVIEW LETTERS Zhao, Z., Sun, X., Fan, S. 2021; 126 (23)
  • Quantum Entanglement and Modulation Enhancement of Free-Electron-Bound-Electron Interaction. Physical review letters Zhao, Z., Sun, X. Q., Fan, S. 2021; 126 (23): 233402

    Abstract

    The modulation and engineering of the free-electron wave function bring new ingredients to the electron-matter interaction. We consider the dynamics of a free-electron passing by a two-level system fully quantum mechanically and study the enhancement of interaction from the modulation of the free-electron wave function. In the presence of resonant modulation of the free-electron wave function, we show that the electron energy loss and gain spectrum is greatly enhanced for a coherent initial state of the two-level system. Thus, a modulated electron can function as a probe of the atomic coherence. We further find that distantly separated two-level atoms can be entangled through interacting with the same free electron. Effects of modulation-induced enhancement can also be observed using a dilute beam of modulated electrons.

    View details for DOI 10.1103/PhysRevLett.126.233402

    View details for PubMedID 34170160

  • Adjoint Method and Inverse Design for Nonlinear Nanophotonic Devices (vol 5, pg 4781, 2018) ACS PHOTONICS Hughes, T. W., Minkov, M., Williamson, I. D., Fan, S. 2021; 8 (5): 1505
  • Deep-Subwavelength Thermal Switch via Resonant Coupling in Monolayer Hexagonal Boron Nitride PHYSICAL REVIEW APPLIED Papadakis, G. T., Ciccarino, C. J., Fan, L., Orenstein, M., Narang, P., Fan, S. 2021; 15 (5)
  • Arbitrary linear transformations for photons in the frequency synthetic dimension. Nature communications Buddhiraju, S., Dutt, A., Minkov, M., Williamson, I. A., Fan, S. 2021; 12 (1): 2401

    Abstract

    Arbitrary linear transformations are of crucial importance in a plethora of photonic applications spanning classical signal processing, communication systems, quantum information processing and machine learning. Here, we present a photonic architecture to achieve arbitrary linear transformations by harnessing the synthetic frequency dimension of photons. Our structure consists of dynamically modulated micro-ring resonators that implement tunable couplings between multiple frequency modes carried by a single waveguide. By inverse design of these short- and long-range couplings using automatic differentiation, we realize arbitrary scattering matrices in synthetic space between the input and output frequency modes with near-unity fidelity and favorable scaling. We show that the same physical structure can be reconfigured to implement a wide variety of manipulations including single-frequency conversion, nonreciprocal frequency translations, and unitary as well as non-unitary transformations. Our approach enables compact, scalable and reconfigurable integrated photonic architectures to achieve arbitrary linear transformations in both the classical and quantum domains using current state-of-the-art technology.

    View details for DOI 10.1038/s41467-021-22670-7

    View details for PubMedID 33893284

  • Publisher Correction: Topological optical differentiator. Nature communications Zhu, T., Guo, C., Huang, J., Wang, H., Orenstein, M., Ruan, Z., Fan, S. 2021; 12 (1): 2209

    View details for DOI 10.1038/s41467-021-22493-6

    View details for PubMedID 33828094

  • Control of non-equilibrium Casimir force APPLIED PHYSICS LETTERS Iizuka, H., Fan, S. 2021; 118 (14)

    View details for DOI 10.1063/5.0043100

    View details for Web of Science ID 000636953100001

  • Effect of Coulomb interaction on the transient optical response of electrons in field-coupled quantum dots PHYSICAL REVIEW A Lu, X., Huang, D., Fan, S. 2021; 103 (4)
  • Theory for Twisted Bilayer Photonic Crystal Slabs. Physical review letters Lou, B., Zhao, N., Minkov, M., Guo, C., Orenstein, M., Fan, S. 2021; 126 (13): 136101

    Abstract

    We analyze scattering properties of twisted bilayer photonic crystal slabs through a high-dimensional plane wave expansion method. The method is applicable for arbitrary twist angles and does not suffer from the limitations of the commonly used supercell approximation. We show strongly tunable resonance properties of this system which can be accounted for semianalytically from a correspondence relation to a simpler structure. We also observe strongly tunable resonant chiral behavior in this system. Our work provides the theoretical foundation for predicting and understanding the rich optical physics of twisted multilayer photonic crystal systems.

    View details for DOI 10.1103/PhysRevLett.126.136101

    View details for PubMedID 33861130

  • Wide wavelength-tunable narrow-band thermal radiation from moire patterns APPLIED PHYSICS LETTERS Guo, C., Guo, Y., Lou, B., Fan, S. 2021; 118 (13)

    View details for DOI 10.1063/5.0047308

    View details for Web of Science ID 000636372600002

  • Photonic Chern insulators from two-dimensional atomic lattices interacting with a single surface plasmon polariton PHYSICAL REVIEW B Rituraj, Orenstein, M., Fan, S. 2021; 103 (12)
  • Nondissipative non-Hermitian dynamics and exceptional points in coupled optical parametric oscillators OPTICA Roy, A., Jahani, S., Guo, Q., Dutt, A., Fan, S., Miri, M., Marandi, A. 2021; 8 (3): 415–21
  • Atomic-Scale Control of Coherent Thermal Radiation ACS PHOTONICS Zhao, B., Song, J., Brongersma, M., Fan, S. 2021; 8 (3): 872–78
  • Transforming heat transfer with thermal metamaterials and devices NATURE REVIEWS MATERIALS Li, Y., Li, W., Han, T., Zheng, X., Li, J., Li, B., Fan, S., Qiu, C. 2021
  • Doubly-Resonant Photonic Crystal Cavities for Efficient Second-Harmonic Generation in III-V Semiconductors. Nanomaterials (Basel, Switzerland) Zanotti, S., Minkov, M., Fan, S., Andreani, L. C., Gerace, D. 2021; 11 (3)

    Abstract

    Second-order nonlinear effects, such as second-harmonic generation, can be strongly enhanced in nanofabricated photonic materials when both fundamental and harmonic frequencies are spatially and temporally confined. Practically designing low-volume and doubly-resonant nanoresonators in conventional semiconductor compounds is challenging owing to their intrinsic refractive index dispersion. In this work we review a recently developed strategy to design doubly-resonant nanocavities with low mode volume and large quality factor via localized defects in a photonic crystal structure. We built on this approach by applying an evolutionary optimization algorithm in connection with Maxwell equations solvers; the proposed design recipe can be applied to any material platform. We explicitly calculated the second-harmonic generation efficiency for doubly-resonant photonic crystal cavity designs in typical III-V semiconductor materials, such as GaN and AlGaAs, while targeting a fundamental harmonic at telecom wavelengths and fully accounting for the tensor nature of the respective nonlinear susceptibilities. These results may stimulate the realization of small footprint photonic nanostructures in leading semiconductor material platforms to achieve unprecedented nonlinear efficiencies.

    View details for DOI 10.3390/nano11030605

    View details for PubMedID 33670997

  • Interaction of two-dimensional atomic lattices with a single surface plasmon polariton PHYSICAL REVIEW A Rituraj, Orenstein, M., Fan, S. 2021; 103 (2)
  • Self-Focused Thermal Emission and Holography Realized by Mesoscopic Thermal Emitters ACS PHOTONICS Zhou, M., Khoram, E., Liu, D., Liu, B., Fan, S., Povinelli, M. L., Yu, Z. 2021; 8 (2): 497–504
  • Topological optical differentiator. Nature communications Zhu, T., Guo, C., Huang, J., Wang, H., Orenstein, M., Ruan, Z., Fan, S. 2021; 12 (1): 680

    Abstract

    Optical computing holds significant promise of information processing with ultrahigh speed and low power consumption. Recent developments in nanophotonic structures have generated renewed interests due to the prospects of performing analog optical computing with compact devices. As one prominent example, spatial differentiation has been demonstrated with nanophotonic structures and directly applied for edge detection in image processing. However, broadband isotropic two-dimensional differentiation, which is required in most imaging processing applications, has not been experimentally demonstrated yet. Here, we establish a connection between two-dimensional optical spatial differentiation and a nontrivial topological charge in the optical transfer function. Based on this connection, we experimentally demonstrate an isotropic two-dimensional differentiation with a broad spectral bandwidth, by using the simplest photonic device, i.e. a single unpatterned interface. Our work indicates that exploiting concepts from topological photonics can lead to new opportunities in optical computing.

    View details for DOI 10.1038/s41467-021-20972-4

    View details for PubMedID 33514708

  • Nighttime Radiative Cooling for Water Harvesting from Solar Panels ACS PHOTONICS Li, W., Dong, M., Fan, L., John, J., Chen, Z., Fan, S. 2021; 8 (1): 269–75
  • Exterior tuning and switching of non-equilibrium Casimir force JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS Iizuka, H., Fan, S. 2021; 38 (1): 151–58
  • Topological complex-energy braiding of non-Hermitian bands. Nature Wang, K., Dutt, A., Wojcik, C. C., Fan, S. 2021; 598 (7879): 59-64

    Abstract

    Effects connected with the mathematical theory of knots1 emerge in many areas of science, from physics2,3 to biology4. Recent theoretical work discovered that the braid group characterizes the topology of non-Hermitian periodic systems5, where the complex band energies can braid in momentum space. However, such braids of complex-energy bands have not been realized or controlled experimentally. Here, we introduce a tight-binding lattice model that can achieve arbitrary elements in the braid group of two strands 𝔹2. We experimentally demonstrate such topological complex-energy braiding of non-Hermitian bands in a synthetic dimension6,7. Our experiments utilize frequency modes in two coupled ring resonators, one of which undergoes simultaneous phase and amplitude modulation. We observe a wide variety of two-band braiding structures that constitute representative instances of links and knots, including the unlink, the unknot, the Hopf link and the trefoil. We also show that the handedness of braids can be changed. Our results provide a direct demonstration of the braid-group characterization of non-Hermitian topology and open a pathway for designing and realizing topologically robust phases in open classical and quantum systems.

    View details for DOI 10.1038/s41586-021-03848-x

    View details for PubMedID 34616054

  • Photonic Modal Circulator Using Temporal Refractive-Index Modulation with Spatial Inversion Symmetry. Physical review letters Wang, J., Herrmann, J. F., Witmer, J. D., Safavi-Naeini, A. H., Fan, S. 2021; 126 (19): 193901

    Abstract

    It has been demonstrated that dynamic refractive-index modulation, which breaks time-reversal symmetry, can be used to create on-chip nonreciprocal photonic devices. In order to achieve amplitude nonreciprocity, all such devices moreover require modulations that break spatial symmetries, which adds complexity in implementations. Here we introduce a modal circulator, which achieves amplitude nonreciprocity through a circulation motion among three modes. We show that such a circulator can be achieved in a dynamically modulated structure that preserves mirror symmetry, and as a result can be implemented using only a single standing-wave modulator, which significantly simplifies the implementation of dynamically modulated nonreciprocal devices. We also prove that in terms of the number of modes involved in the transport process, the modal circulator represents the minimum configuration in which complete amplitude nonreciprocity can be achieved while preserving spatial symmetry.

    View details for DOI 10.1103/PhysRevLett.126.193901

    View details for PubMedID 34047603

  • Quantum entanglement and modulation enhancement of free-electron-bound-electron interaction Zhao, Z., Sun, X., Fan, S., IEEE IEEE. 2021
  • Teleportation-Based Photonic Quantum Computing Using a Single Controllable Qubit Bartlett, B., Dutt, A., Fan, S., IEEE IEEE. 2021
  • Photonic arbitrary linear transformations in the frequency synthetic dimension Buddhiraju, S., Dutt, A., Minkov, M., Williamson, I. D., Fan, S., IEEE IEEE. 2021
  • Fabrication of Photonic Crystal Surface Emitting Lasers (PCSELs) by Epitaxial Regrowth Reilly, K., Kalapala, A., Song, A., Rotter, T., Liu, Z., Renteria, E., Fan, S., Zhou, W., Balakrishnan, G., IEEE IEEE. 2021
  • Photonic Topological Dissipation in Time-Multiplexed Resonator Networks Leefmans, C., Dutt, A., Williams, J., Yuan, L., Parto, M., Nori, F., Fan, S., Marandi, A., IEEE IEEE. 2021
  • Manipulating Single Surface Plasmon Polariton via Tailored Atom-Photon Interaction Rituraj, Orenstein, M., Fan, S., IEEE IEEE. 2021
  • Photonic modal circulator using dynamic modulation with mirror symmetry Wang, J., Herrmann, J., Witmer, J., Safavi-Naeini, A. H., Fan, S., IEEE IEEE. 2021
  • Design of Nighttime Power Generation System to Optimally Utilize Outer Space Darkness Fan, L., Li, W., Jin, W., Orenstein, M., Fan, S., IEEE IEEE. 2021
  • Photonic Meron Spin Texture in Momentum Space Guo, C., Xiao, M., Guo, Y., Yuan, L., Fan, S., IEEE IEEE. 2021
  • Experimental Demonstration of Dynamic Band Structure Measurement along a Synthetic Dimension Li, G., Zheng, Y., Dutt, A., Yu, D., Shan, Q., Liu, S., Yuan, L., Fan, S., Chen, X., IEEE IEEE. 2021
  • Design principles of apodized grating couplers Zhao, Z., Fan, S., IEEE IEEE. 2021
  • Arbitrary control and direct measurement of topological windings of a non-Hermitian band Wang, K., Dutt, A., Yang, K., Wojcik, C. C., Vuckovic, J., Fan, S., IEEE IEEE. 2021
  • Generating arbitrary topological windings of a non-Hermitian band. Science (New York, N.Y.) Wang, K., Dutt, A., Yang, K. Y., Wojcik, C. C., Vuckovic, J., Fan, S. 2021; 371 (6535): 1240–45

    Abstract

    The nontrivial topological features in the energy band of non-Hermitian systems provide promising pathways to achieve robust physical behaviors in classical or quantum open systems. A key topological feature of non-Hermitian systems is the nontrivial winding of the energy band in the complex energy plane. We provide experimental demonstrations of such nontrivial winding by implementing non-Hermitian lattice Hamiltonians along a frequency synthetic dimension formed in a ring resonator undergoing simultaneous phase and amplitude modulations, and by directly characterizing the complex band structures. Moreover, we show that the topological winding can be controlled by changing the modulation waveform. Our results allow for the synthesis and characterization of topologically nontrivial phases in nonconservative systems.

    View details for DOI 10.1126/science.abf6568

    View details for PubMedID 33737483

  • Dynamic band structure measurement in the synthetic space SCIENCE ADVANCES Li, G., Zheng, Y., Dutt, A., Yu, D., Shan, Q., Liu, S., Yuan, L., Fan, S., Chen, X. 2021; 7 (2)

    Abstract

    Band structure theory plays an essential role in exploring physics in both solid-state systems and photonics. Here, we demonstrate a direct experimental measurement of the dynamic band structure in a synthetic space including the frequency axis of light, realized in a ring resonator under near-resonant dynamic modulation. This synthetic lattice exhibits the physical picture of the evolution of the wave vector reciprocal to the frequency axis in the band structure, analogous to a one-dimensional lattice under an external force. We experimentally measure the trajectories of the dynamic band structure by selectively exciting the band with a continuous wave source with its frequency scanning across the entire energy regime of the band. Our results not only provide a new perspective for exploring the dynamics in fundamental physics of solid-state and photonic systems with the concept of the synthetic dimension but also enable great capability in band structure engineering in photonics.

    View details for DOI 10.1126/sciadv.abe4335

    View details for Web of Science ID 000606331400044

    View details for PubMedID 33524000

    View details for PubMedCentralID PMC7793575

  • Integrated thin-film lithium niobate non-reciprocal circulator Herrmann, J. F., Ansari, V., Wang, J., Witmer, J. D., Fan, S., Safavi-Naeini, A. H., IEEE IEEE. 2021
  • Inverse design of relativistic lightsail for efficient propulsion Jin, W., Li, W., Orenstein, M., Fan, S., IEEE IEEE. 2021
  • Scattering of a single plasmon polariton by multiple atoms for in-plane control of light NANOPHOTONICS Rituraj, Orenstein, M., Fan, S. 2021; 10 (1): 579–87
  • Three-Dimensional Printable Nanoporous Polymer Matrix Composites for Daytime Radiative Cooling. Nano letters Zhou, K. n., Li, W. n., Patel, B. B., Tao, R. n., Chang, Y. n., Fan, S. n., Diao, Y. n., Cai, L. n. 2021

    Abstract

    Daytime radiative cooling presents an exciting new strategy for combating global warming, because it can passively cool buildings by reflecting sunlight and utilizing the infrared atmospheric window to eject heat into outer space. Recent progress with novel material designs showed promising subambient cooling performance under direct sunlight. However, large-scale implementation of radiative cooling technologies is still limited by the high-cost and complex fabrication. Here, we develop a nanoporous polymer matrix composite (PMC) to enable rapid production and cost reduction using commercially available polymer processing techniques, such as molding, extrusion, and 3D printing. With a high solar reflectance of 96.2% and infrared emissivity > 90%, the nanoporous PMC achieved a subambient temperature drop of 6.1 °C and cooling power of 85 W/m2 under direct sunlight, which are comparable to the state-of-the-art. This work offers great promise to make radiative cooling technologies more viable for saving energy and reducing emissions in building cooling applications.

    View details for DOI 10.1021/acs.nanolett.0c04810

    View details for PubMedID 33464912

  • Nonreciprocity in Bianisotropic Systems with Uniform Time Modulation. Physical review letters Wang, X., Ptitcyn, G., Asadchy, V. S., Díaz-Rubio, A., Mirmoosa, M. S., Fan, S., Tretyakov, S. A. 2020; 125 (26): 266102

    Abstract

    Physical systems with material properties modulated in time provide versatile routes for designing magnetless nonreciprocal devices. Traditionally, nonreciprocity in such systems is achieved exploiting both temporal and spatial modulations, which inevitably requires a series of time-modulated elements distributed in space. In this Letter, we introduce a concept of bianisotropic time-modulated systems capable of nonreciprocal wave propagation at the fundamental frequency and based on uniform, solely temporal material modulations. In the absence of temporal modulations, the considered bianisotropic systems are reciprocal. We theoretically explain the nonreciprocal effect by analyzing wave propagation in an unbounded bianisotropic time-modulated medium. The effect stems from temporal modulation of spatial dispersion effects which to date were not taken into account in previous studies based on the local-permittivity description. We propose a circuit design of a bianisotropic metasurface that can provide phase-insensitive isolation and unidirectional amplification.

    View details for DOI 10.1103/PhysRevLett.125.266102

    View details for PubMedID 33449712

  • Nonreciprocity in Bianisotropic Systems with Uniform Time Modulation PHYSICAL REVIEW LETTERS Wang, X., Ptitcyn, G., Asadchy, V. S., Diaz-Rubio, A., Mirmoosa, M. S., Fan, S., Tretyakov, S. A. 2020; 125 (26)
  • Inference in artificial intelligence with deep optics and photonics. Nature Wetzstein, G., Ozcan, A., Gigan, S., Fan, S., Englund, D., Soljacic, M., Denz, C., Miller, D. A., Psaltis, D. 2020; 588 (7836): 39–47

    Abstract

    Artificial intelligence tasks across numerous applications require accelerators for fast and low-power execution. Optical computing systems may be able to meet these domain-specific needs but, despite half a century of research, general-purpose optical computing systems have yet to mature into a practical technology. Artificial intelligence inference, however, especially for visual computing applications, may offer opportunities for inference based on optical and photonic systems. In this Perspective, we review recent work on optical computing for artificial intelligence applications and discuss its promise and challenges.

    View details for DOI 10.1038/s41586-020-2973-6

    View details for PubMedID 33268862

  • Radiative Thermal Router Based on Tunable Magnetic Weyl Semimetals ACS PHOTONICS Guo, C., Zhao, B., Huang, D., Fan, S. 2020; 7 (11): 3257–63
  • Scalable and hierarchically designed polymer film as a selective thermal emitter for high-performance all-day radiative cooling. Nature nanotechnology Li, D., Liu, X., Li, W., Lin, Z., Zhu, B., Li, Z., Li, J., Li, B., Fan, S., Xie, J., Zhu, J. 2020

    Abstract

    Traditional cooling systems consume tremendous amounts of energy and thus aggravate the greenhouse effect1,2. Passive radiative cooling, dissipating an object's heat through an atmospheric transparency window (8-13mum) to outer space without any energy consumption, has attracted much attention3-9. The unique feature of radiative cooling lies in the high emissivity in the atmospheric transparency window through which heat can be dissipated to the universe. Therefore, for achieving high cooling performance, the design and fabrication of selective emitters, with emission strongly dominant in the transparency window, is of essential importance, as such spectral selection suppresses parasitic absorption from the surrounding thermal radiation. Recently, various materials and structures with tailored spectrum responses have been investigated to achieve the effect of daytime radiative cooling6-8,10-15. However, most of the radiative cooling materials reported possess broad-band absorption/emission covering the whole mid-infrared wavelength11-15. Here we demonstrate that a hierarchically designed polymer nanofibre-based film, produced by a scalable electrostatic spinning process, enables selective mid-infrared emission, effective sunlight reflection and therefore excellent all-day radiative cooling performance. Specifically, the C-O-C (1,260-1,110cm-1) and C-OH (1,239-1,030cm-1) bonding endows the selective emissivity of 78% in 8-13mum wavelength range, and the design of nanofibres with a controlled diameter allows for a high reflectivity of 96.3% in 0.3-2.5mum wavelength range. As a result, we observe ~3°C cooling improvement of this selective thermal emitter as compared to that of a non-selective emitter at night, and 5°C sub-ambient cooling under sunlight. The impact of this hierarchically designed selective thermal emitter on alleviating global warming and temperature regulating an Earth-like planet is also analysed, with a significant advantage demonstrated. With its excellent cooling performance and a scalable process, this hierarchically designed selective thermal emitter opens a new pathway towards large-scale applications of all-day radiative cooling materials.

    View details for DOI 10.1038/s41565-020-00800-4

    View details for PubMedID 33199884

  • Operating modes of dual-grating dielectric laser accelerators PHYSICAL REVIEW ACCELERATORS AND BEAMS Black, D. S., Zhao, Z., Leedle, K. J., Miao, Y., Byer, R. L., Fan, S., Solgaard, O. 2020; 23 (11)
  • Beating absorption in solid-state high harmonics COMMUNICATIONS PHYSICS Liu, H., Vampa, G., Zhang, J., Shi, Y., Buddhiraju, S., Fan, S., Vuckovic, J., Bucksbaum, P. H., Reis, D. A. 2020; 3 (1)
  • Integrated Nonreciprocal Photonic Devices With Dynamic Modulation PROCEEDINGS OF THE IEEE Williamson, B. D., Minkov, M., Dutt, A., Wang, J., Song, A. Y., Fan, S. 2020; 108 (10): 1759–84
  • Tutorial on Electromagnetic Nonreciprocity and its Origins PROCEEDINGS OF THE IEEE Asadchy, V. S., Mirmoosa, M., Diaz-Rubio, A., Fan, S., Tretyakov, S. A. 2020; 108 (10): 1684–1727
  • Design of a multichannel photonic crystal dielectric laser accelerator PHOTONICS RESEARCH Zhao, Z., Black, D. S., England, R., Hughes, T. W., Miao, Y., Solgaard, O., Byer, R. L., Fan, S. 2020; 8 (10): 1586–98

    View details for DOI 10.1364/PRJ.394127

    View details for Web of Science ID 000577372300009

  • Doubly resonant second-harmonic generation of a vortex beam from a bound state in the continuum OPTICA Wang, J., Clementi, M., Minkov, M., Barone, A., Carlin, J., Grandjean, N., Gerace, D., Fan, S., Galli, M., Houdre, R. 2020; 7 (9): 1126–32
  • Squeeze free space with nonlocal flat optics OPTICA Guo, C., Wang, H., Fan, S. 2020; 7 (9): 1133–38
  • Inverse Design of Lightweight Broadband Reflector for Relativistic Lightsail Propulsion ACS PHOTONICS Jin, W., Li, W., Orenstein, M., Fan, S. 2020; 7 (9): 2350–55
  • Creating an Eco-Friendly Building Coating with Smart Subambient Radiative Cooling. Advanced materials (Deerfield Beach, Fla.) Xue, X., Qiu, M., Li, Y., Zhang, Q. M., Li, S., Yang, Z., Feng, C., Zhang, W., Dai, J., Lei, D., Jin, W., Xu, L., Zhang, T., Qin, J., Wang, H., Fan, S. 2020: e1906751

    Abstract

    Subambient daytime radiative cooling (SDRC) provides a promising electricity- and cryogen-free pathway for global energy-efficiency. However, current SDRC systems require stringent surface designs, which are neither cost-effective nor eco-friendly, to selectively emit thermal radiation to outer space and simultaneously maximize solar reflectance. Here, a generic method is developed to upgrade the conventional building-coating materials with a peculiar self-adaptive SDRC effect through combining particle scattering, sunlight-excited fluorescence, and mid-infrared broadband radiation. It is also theoretically proved that heat exchange with the sky can eliminate the use of resonant microstructures and noble metal mirrors in conventional SDRC, and also leads to enhanced daytime cooling yet suppressed nighttime overcooling. When exposed to direct sunlight, the upgraded coating over an aluminum plate can achieve 6 °C (7 °C on a scale-model building) below the ambient temperature under a solar intensity of 744 W m-2 (850 W m-2 ), yielding a cooling power of 84.2 W m-2 . The results pave the way for practical large-scale applications of high-performance SDRC for human thermal comfort in buildings.

    View details for DOI 10.1002/adma.201906751

    View details for PubMedID 32924184

  • Analytic and geometric properties of scattering from periodically modulated quantum-optical systems PHYSICAL REVIEW A Trivedi, R., White, A., Fan, S., Vuckovic, J. 2020; 102 (3)
  • Parallel Programming of an Arbitrary Feedforward Photonic Network IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS Pai, S., Williamson, I. D., Hughes, T. W., Minkov, M., Solgaard, O., Fan, S., Miller, D. B. 2020; 26 (5)
  • Creating locally interacting Hamiltonians in the synthetic frequency dimension for photons PHOTONICS RESEARCH Yuan, L., Dutt, A., Qin, M., Fan, S., Chen, X. 2020; 8 (9): B8–B14

    View details for DOI 10.1364/PRJ.396731

    View details for Web of Science ID 000565856300004

  • Experimental demonstration of silicon photonic devices optimized by a flexible and deterministic pixel-by-pixel technique APPLIED PHYSICS LETTERS Boutami, S., Hassan, K., Dupre, C., Baud, L., Fan, S. 2020; 117 (7)

    View details for DOI 10.1063/5.0013558

    View details for Web of Science ID 000564165800001

  • Maximal nighttime electrical power generation via optimal radiative cooling OPTICS EXPRESS Fan, L., Li, W., Jin, W., Orenstein, M., Fan, S. 2020; 28 (17): 25460–70

    Abstract

    We present a systematic optimization of nighttime thermoelectric power generation system utilizing radiative cooling. We show that an electrical power density >2 W/m2, two orders of magnitude higher than the previously reported experimental result, is achievable using existing technologies. This system combines radiative cooling and thermoelectric power generation and operates at night when solar energy harvesting is unavailable. The thermoelectric power generator (TEG) itself covers less than 1 percent of the system footprint area when achieving this optimal power generation, showing economic feasibility. We study the influence of emissivity spectra, thermal convection, thermoelectric figure of merit and the area ratio between the TEG and the radiative cooler on the power generation performance. We optimize the thermal radiation emitter attached to the cold side and propose practical material implementation. The importance of the optimal emitter is elucidated by the gain of 153% in power density compared to regular blackbody emitters.

    View details for DOI 10.1364/OE.397714

    View details for Web of Science ID 000560936200091

    View details for PubMedID 32907066

  • Design Principles of Apodized Grating Couplers JOURNAL OF LIGHTWAVE TECHNOLOGY Zhao, Z., Fan, S. 2020; 38 (16): 4435–46
  • Theoretical constraints on reciprocal and non-reciprocal many-body radiative heat transfer PHYSICAL REVIEW B Guo, C., Fan, S. 2020; 102 (8)
  • Single-Photon Transport in a Topological Waveguide from a Dynamically Modulated Photonic System PHYSICAL REVIEW APPLIED Wang, L., Yuan, L., Chen, X., Fan, S. 2020; 14 (1)
  • PT-Symmetric Topological Edge-Gain Effect. Physical review letters Song, A. Y., Sun, X. Q., Dutt, A., Minkov, M., Wojcik, C., Wang, H., Williamson, I. A., Orenstein, M., Fan, S. 2020; 125 (3): 033603

    Abstract

    We demonstrate a non-Hermitian topological effect that is characterized by having complex eigenvalues only in the edge states of a topological material, despite the fact that the material is completely uniform. Such an effect can be constructed in any topological structure formed by two gapped subsystems, e.g., a quantum spin-Hall system, with a suitable non-Hermitian coupling between the spins. The resulting complex-eigenvalued edge state is robust against defects due to the topological protection. In photonics, such an effect can be used for the implementation of topological lasers, in which a uniform pumping provides gain only in the edge lasing state. Furthermore, such a topological lasing model is reciprocal and is thus compatible with standard photonic platforms.

    View details for DOI 10.1103/PhysRevLett.125.033603

    View details for PubMedID 32745404

  • Two-level quantum system as a macroscopic scatterer for ultraconfined two-dimensional photonic modes PHYSICAL REVIEW A Rituraj, Orenstein, M., Fan, S. 2020; 102 (1)
  • Inverse Design of Photonic Crystals through Automatic Differentiation ACS PHOTONICS Minkov, M., Williamson, I. D., Andreani, L. C., Gerace, D., Lou, B., Song, A. Y., Hughes, T. W., Fan, S. 2020; 7 (7): 1729–41
  • PT-Symmetric Topological Edge-Gain Effect PHYSICAL REVIEW LETTERS Song, A. Y., Sun, X., Dutt, A., Minkov, M., Wojcik, C., Wang, H., Williamson, I., Orenstein, M., Fan, S. 2020; 125 (3)
  • Bounds for Scattering from Absorptionless Electromagnetic Structures PHYSICAL REVIEW APPLIED Trivedi, R., Angeris, G., Su, L., Boyd, S., Fan, S., Vuckovic, J. 2020; 14 (1)
  • Nonreciprocal Metamaterial Obeying Time-Reversal Symmetry. Physical review letters Buddhiraju, S., Song, A., Papadakis, G. T., Fan, S. 2020; 124 (25): 257403

    Abstract

    We introduce a class of non-Hermitian systems that break electromagnetic reciprocity while preserving time-reversal symmetry, and describe its novel polarization dynamics. We show that this class of systems can be realized using van der Waals heterostructures involving transition-metal dichalcogenides (TMDs). Our work provides a path towards achieving strong optical nonreciprocity and polarization-dependent directional amplification using compact, large-area and magnet-free structures.

    View details for DOI 10.1103/PhysRevLett.124.257403

    View details for PubMedID 32639792

  • Nonreciprocal Metamaterial Obeying Time-Reversal Symmetry PHYSICAL REVIEW LETTERS Buddhiraju, S., Song, A., Papadakis, G. T., Fan, S. 2020; 124 (25)
  • Alice strings in non-Hermitian systems PHYSICAL REVIEW RESEARCH Sun, X., Wojcik, C. C., Fan, S., Bzdusek, T. 2020; 2 (2)
  • Sub-Wavelength Passive Optical Isolators Using Photonic Structures Based on Weyl Semimetals ADVANCED OPTICAL MATERIALS Asadchy, V. S., Guo, C., Zhao, B., Fan, S. 2020
  • Controlling the dopant profile for SRH suppression at low current densities in lambda approximate to 1330nm GaInAsP light-emitting diodes APPLIED PHYSICS LETTERS Santhanam, P., Li, W., Zhao, B., Rogers, C., Gray, D., Jahelka, P., Atwater, H. A., Fan, S. 2020; 116 (20)

    View details for DOI 10.1063/5.0002058

    View details for Web of Science ID 000537237300001

  • Homotopy characterization of non-Hermitian Hamiltonians PHYSICAL REVIEW B Wojcik, C. C., Sun, X., Bzdusek, T., Fan, S. 2020; 101 (20)
  • Retarded Charge-Carrier Recombination in Photoelectrochemical Cells from Plasmon-Induced Resonance Energy Transfer ADVANCED ENERGY MATERIALS Choi, Y., Lee, B., Jung, M., Han, H., Kim, S., Chen, K., Kim, D., Heinz, T. F., Fan, S., Lee, J., Yi, G., Kim, J., Park, J. 2020
  • Robust and efficient wireless power transfer using a switch-mode implementation of a nonlinear parity-time symmetric circuit NATURE ELECTRONICS Assawaworrarit, S., Fan, S. 2020
  • Experimental realization of arbitrary activation functions for optical neural networks OPTICS EXPRESS Frad, M., Williamson, I. D., Edwards, M., Liu, K., Pai, S., Bartlett, B., Minkov, M., Hughes, T. W., Fan, S., Nguyen, T. 2020; 28 (8): 12138–48

    View details for DOI 10.1364/OE.391473

    View details for Web of Science ID 000526518300118

  • Non-reciprocal polarization rotation using dynamic refractive index modulation OPTICS EXPRESS Wang, J., Shi, Y., Fan, S. 2020; 28 (8): 11974–82

    View details for DOI 10.1364/OE.389357

    View details for Web of Science ID 000526518300103

  • Inverse-designed non-reciprocal pulse router for chip-based LiDAR NATURE PHOTONICS Yang, K., Skarda, J., Cotrufo, M., Dutt, A., Ahn, G., Sawaby, M., Vercruysse, D., Arbabian, A., Fan, S., Alu, A., Vuckovic, J. 2020
  • Meron Spin Textures in Momentum Space. Physical review letters Guo, C., Xiao, M., Guo, Y., Yuan, L., Fan, S. 2020; 124 (10): 106103

    Abstract

    We show that a momentum-space meron spin texture for electromagnetic fields in free space can be generated by controlling the interaction of light with a photonic crystal slab having a nonzero Berry curvature. These spin textures in momentum space have not been previously noted either in electronic or photonic systems. Breaking the inversion symmetry of a honeycomb photonic crystal gaps out the Dirac cones at the corners of Brillouin zone. The pseudospin textures of photonic bands near the gaps exhibit a meron or antimeron. Unlike the electronic systems, the pseudospin texture of the photonic modes manifests directly in the spin (polarization) texture of the leakage radiation, as the Dirac points can be above the light line. Such a spin texture provides a direct approach to visualize the local Berry curvature. Our work highlights the significant opportunities of using photonic structures for the exploration of topological spin textures, with potential applications towards topologically robust ways to manipulate polarizations and other modal characteristics of light.

    View details for DOI 10.1103/PhysRevLett.124.106103

    View details for PubMedID 32216415

  • Meron Spin Textures in Momentum Space PHYSICAL REVIEW LETTERS Guo, C., Xiao, M., Guo, Y., Yuan, L., Fan, S. 2020; 124 (10)
  • Fundamental Limits of the Dew-Harvesting Technology NANOSCALE AND MICROSCALE THERMOPHYSICAL ENGINEERING Dong, M., Zhang, Z., Shi, Y., Zhao, X., Fan, S., Chen, Z. 2020
  • Nonreciprocal radiative heat transfer between two planar bodies PHYSICAL REVIEW B Fan, L., Guo, Y., Papadakis, G. T., Zhao, B., Zhao, Z., Buddhiraju, S., Orenstein, M., Fan, S. 2020; 101 (8)
  • Compact Incoherent Image Differentiation with Nanophotonic Structures ACS PHOTONICS Wang, H., Guo, C., Zhao, Z., Fan, S. 2020; 7 (2): 338–43
  • Determining the optimal learning rate in gradient-based electromagnetic optimization using the Shanks transformation in the Lippmann-Schwinger formalism OPTICS LETTERS Boutami, S., Zhao, N., Fan, S. 2020; 45 (3): 595–98

    Abstract

    In gradient-based optimization of photonic devices, within the overall design parameter space, one iteratively performs a line search in a one-dimensional subspace as spanned by the search direction. While the search direction can be efficiently determined with the adjoint variable method, there has not been an efficient algorithm that determines the optimal learning rate that controls the distance one moves along the search direction. Here we introduce an efficient algorithm of determining the optimal learning rate, using the Shanks transformation in the Lippmann-Schwinger formalism. Our approach can determine very accurately the optimal learning rates at each epoch, with only a modest increase of computational cost. We show that this approach can significantly improve the figure of merits of the final structure, as compared to conventional methods for estimating the learning rate.

    View details for DOI 10.1364/OL.379375

    View details for Web of Science ID 000510869500001

    View details for PubMedID 32004260

  • Design of a multi-channel photonic crystal dielectric laser accelerator Zhao, Z., Black, D. S., England, R., Hughes, T. W., Miao, Y., Solgaard, O., Byer, R. L., Fan, S., IEEE IEEE. 2020
  • Efficient and Robust Wireless Power Transfer based on Parity-Time Symmetry Assawaworrarit, S., Fan, S., Belov, P., Petrov, M. AMER INST PHYSICS. 2020

    View details for DOI 10.1063/5.0031691

    View details for Web of Science ID 000656159400007

  • Higher-order topological insulators in synthetic dimensions. Light, science & applications Dutt, A., Minkov, M., Williamson, I. A., Fan, S. 2020; 9 (1): 131

    Abstract

    Conventional topological insulators support boundary states with dimension one lower than that of the bulk system that hosts them, and these states are topologically protected due to quantized bulk dipole moments. Recently, higher-order topological insulators have been proposed as a way of realizing topological states with dimensions two or more lower than that of the bulk due to the quantization of bulk quadrupole or octupole moments. However, all these proposals as well as experimental realizations have been restricted to real-space dimensions. Here, we construct photonic higher-order topological insulators (PHOTIs) in synthetic dimensions. We show the emergence of a quadrupole PHOTI supporting topologically protected corner modes in an array of modulated photonic molecules with a synthetic frequency dimension, where each photonic molecule comprises two coupled rings. By changing the phase difference of the modulation between adjacent coupled photonic molecules, we predict a dynamical topological phase transition in the PHOTI. Furthermore, we show that the concept of synthetic dimensions can be exploited to realize even higher-order multipole moments such as a fourth-order hexadecapole (16-pole) insulator supporting 0D corner modes in a 4D hypercubic synthetic lattice that cannot be realized in real-space lattices.

    View details for DOI 10.1038/s41377-020-0334-8

    View details for PubMedID 34282115

  • Thermodynamic limits for simultaneous energy harvesting from the hot sun and cold outer space. Light, science & applications Li, W. n., Buddhiraju, S. n., Fan, S. n. 2020; 9 (1): 68

    Abstract

    The sun and outer space are two of the most important fundamental thermodynamic resources for renewable energy harvesting. A significant amount of work has focused on understanding the fundamental limit of energy harvesting from the sun. More recently, there have been several theoretical analyses of the fundamental limit of energy harvesting from outer space. However, far less is understood about the fundamental limits of simultaneous energy harvesting from both the sun and outer space. Here, we consider and introduce various schemes that are capable of simultaneous energy harvesting and elucidate the fundamental thermodynamic limits of these schemes. We show that the theoretical limits can far exceed the previously established limit associated with utilizing only one thermodynamic resource. Our results highlight the significant potential of simultaneous energy harvesting and indicate new fundamental opportunities for improving the efficiency of energy harvesting systems.

    View details for DOI 10.1038/s41377-020-0296-x

    View details for PubMedID 33893271

  • Integrated near-field thermo-photovoltaics for heat recycling. Nature communications Bhatt, G. R., Zhao, B. n., Roberts, S. n., Datta, I. n., Mohanty, A. n., Lin, T. n., Hartmann, J. M., St-Gelais, R. n., Fan, S. n., Lipson, M. n. 2020; 11 (1): 2545

    Abstract

    Energy transferred via thermal radiation between two surfaces separated by nanometer distances can be much larger than the blackbody limit. However, realizing a scalable platform that utilizes this near-field energy exchange mechanism to generate electricity remains a challenge. Here, we present a fully integrated, reconfigurable and scalable platform operating in the near-field regime that performs controlled heat extraction and energy recycling. Our platform relies on an integrated nano-electromechanical system that enables precise positioning of a thermal emitter within nanometer distances from a room-temperature germanium photodetector to form a thermo-photovoltaic cell. We demonstrate over an order of magnitude enhancement of power generation (Pgen ~ 1.25 μWcm-2) in our thermo-photovoltaic cell by actively tuning the gap between a hot-emitter (TE ~ 880 K) and the cold photodetector (TD ~ 300 K) from ~ 500 nm down to ~ 100 nm. Our nano-electromechanical system consumes negligible tuning power (Pgen/PNEMS ~ 104) and relies on scalable silicon-based process technologies.

    View details for DOI 10.1038/s41467-020-16197-6

    View details for PubMedID 32439917

  • Axion-Field-Enabled Nonreciprocal Thermal Radiation in Weyl Semimetals. Nano letters Zhao, B. n., Guo, C. n., Garcia, C. A., Narang, P. n., Fan, S. n. 2020

    Abstract

    Objects around us constantly emit and absorb thermal radiation. The emission and absorption processes are governed by two fundamental radiative properties: emissivity and absorptivity. For reciprocal systems, the emissivity and absorptivity are restricted to be equal by Kirchhoff's law of thermal radiation. This restriction limits the degree of freedom to control thermal radiation and contributes to an intrinsic loss mechanism in photonic energy harvesting systems. Existing approaches to violate Kirchhoff's law typically utilize magneto-optical effects with an external magnetic field. However, these approaches require either a strong magnetic field (∼3T) or narrow-band resonances under a moderate magnetic field (∼0.3T), because the nonreciprocity in conventional magneto-optical effects is weak in the thermal wavelength range. Here, we show that the axion electrodynamics in magnetic Weyl semimetals can be used to construct strongly nonreciprocal thermal emitters that nearly completely violate Kirchhoff's law over broad angular and frequency ranges without requiring any external magnetic field.

    View details for DOI 10.1021/acs.nanolett.9b05179

    View details for PubMedID 32073859

  • Thermodynamic limits for simultaneous energy harvesting from the hot sun and cold outer space. Light, science & applications Li, W. n., Buddhiraju, S. n., Fan, S. n. 2020; 9: 68

    Abstract

    The sun and outer space are two of the most important fundamental thermodynamic resources for renewable energy harvesting. A significant amount of work has focused on understanding the fundamental limit of energy harvesting from the sun. More recently, there have been several theoretical analyses of the fundamental limit of energy harvesting from outer space. However, far less is understood about the fundamental limits of simultaneous energy harvesting from both the sun and outer space. Here, we consider and introduce various schemes that are capable of simultaneous energy harvesting and elucidate the fundamental thermodynamic limits of these schemes. We show that the theoretical limits can far exceed the previously established limit associated with utilizing only one thermodynamic resource. Our results highlight the significant potential of simultaneous energy harvesting and indicate new fundamental opportunities for improving the efficiency of energy harvesting systems.

    View details for DOI 10.1038/s41377-020-0296-x

    View details for PubMedID 32351692

    View details for PubMedCentralID PMC7181797

  • Universal programmable photonic architecture for quantum information processing Physical Review A Bartlett, B., Fan, S. 2020; 101 (4): 042319
  • Efficient second harmonic generation in a doubly resonant photonic crystal cavity based on a bound state in the continuum Wang, J., Clementi, M., Barone, A., Minicoy, M., Carlin, J., Grandjean, N., Fan, S., Houdre, R., Gerace, D., Galli, M., IEEE IEEE. 2020
  • Terrestrial radiative cooling: Using the cold universe as a renewable and sustainable energy source. Science (New York, N.Y.) Yin, X., Yang, R., Tan, G., Fan, S. 2020; 370 (6518): 786–91

    Abstract

    Photonic materials designed at wavelength scales have enabled a range of emerging energy technologies, from solid-state lighting to efficient photovoltaics that have transformed global energy landscapes. Daytime passive radiative cooling materials shed heat from the ground to the cold universe by taking advantage of the terrestrial thermal radiation that is as large as the renewable solar energy. Newly developed photonic materials permit subambient cooling under direct sunshine, and their applications are expanding rapidly enabled by scalable manufacturing. We review here the recent advancement of daytime subambient radiative cooling materials, which allow energy-efficient cooling and are paving the way toward technologies that harvest the coldness from the universe as a new renewable energy source.

    View details for DOI 10.1126/science.abb0971

    View details for PubMedID 33184205

  • Experimental demonstration of acoustic semimetal with topologically charged nodal surface. Science advances Xiao, M. n., Ye, L. n., Qiu, C. n., He, H. n., Liu, Z. n., Fan, S. n. 2020; 6 (8): eaav2360

    Abstract

    Weyl points are zero-dimensional band degeneracy in three-dimensional momentum space that has nonzero topological charges. The presence of the topological charges protects the degeneracy points against perturbations and enables a variety of fascinating phenomena. It is so far unclear whether such charged objects can occur in higher dimensions. Here, we introduce the concept of charged nodal surface, a two-dimensional band degeneracy surface in momentum space that is topologically charged. We provide an effective Hamiltonian for this charged nodal surface and show that such a Hamiltonian can be implemented in a tight-binding model. This is followed by an experimental realization in a phononic crystal. The measured topologically protected surface arc state of such an acoustic semimetal reproduces excellently the full-wave simulations. Creating high-dimensional charged geometric objects in momentum space promises a broad range of unexplored topological physics.

    View details for DOI 10.1126/sciadv.aav2360

    View details for PubMedID 32128388

    View details for PubMedCentralID PMC7034989

  • Photonic Refrigeration from Time-Modulated Thermal Emission. Physical review letters Buddhiraju, S. n., Li, W. n., Fan, S. n. 2020; 124 (7): 077402

    Abstract

    We develop theoretical and computational formalisms to describe thermal radiation from temporally modulated systems. We show that such a modulation results in a photon-based active cooling mechanism. This mechanism has a high thermodynamic performance that can approach the Carnot limit. Our work points to exciting new avenues in active, time-modulated control of thermal emission for cooling and energy harvesting applications.

    View details for DOI 10.1103/PhysRevLett.124.077402

    View details for PubMedID 32142345

  • Broadening Near-Field Emission for Performance Enhancement in Thermophotovoltaics. Nano letters Papadakis, G. T., Buddhiraju, S. n., Zhao, Z. n., Zhao, B. n., Fan, S. n. 2020

    Abstract

    The conventional notion for achieving high efficiency in thermophotovoltaics (TPVs) is to use a monochromatic emission at a photon energy corresponding to the band gap of the cell. Here, we prove theoretically that such a notion is only accurate under idealized conditions and further show that, when nonradiative recombination is taken into account, efficiency improvement can be achieved by broadening the emission spectrum, due to an enhancement in the open-circuit voltage. Broadening the emission spectrum also improves the electrical power density, by increasing the short-circuit current. Hence, broadening the emission spectrum can simultaneously improve the efficiency and power density of practical TPV systems. To illustrate these findings, we focus on surface polariton-mediated near-field TPVs. We propose a versatile design strategy for broadening the emission spectrum via stacking of multiple plasmonic thin film layers. As an example, we consider a realistic ITO/InAs TPV and predict a conversion efficiency of 50% simultaneously with a power density of nearly 80 W/cm2 at a 1300 K emitter temperature. The performance of our proposed system far exceeds previous works in similar systems using a single plasmonic layer emitter.

    View details for DOI 10.1021/acs.nanolett.9b04762

    View details for PubMedID 31978305

  • Photonic Quantum Programmable Gate Arrays Bartlett, B., Fan, S., IEEE IEEE. 2020
  • Nonreciprocal radiative heat transfer between two planar bodies Fan, L., Guo, Y., Papadakis, G. T., Zhao, B., Zhao, Z., Buddhiraju, S., Orenstein, M., Fan, S., IEEE IEEE. 2020
  • Dynamics for encircling an exceptional point in a nonlinear non-Hermitian system Wang, H., Assawaworrarit, S., Fan, S., IEEE IEEE. 2020
  • Active photonic cooling using time-modulated thermal emission Buddhiraju, S., Li, W., Fan, S., IEEE IEEE. 2020
  • Tunable Nonlinear Activation Functions for Optical Neural Networks Williamson, I. D., Hughes, T. W., Minkov, M., Bartlett, B., Pai, S., Fan, S., IEEE IEEE. 2020
  • Inverse-designed optical interconnect based on multimode photonics and mode-division multiplexing Yang, K., Skarda, J., Guidry, M. A., Dutt, A., Fan, S., Vuckovic, J., IEEE IEEE. 2020
  • Broadband Linear-to-Circular Polarization Conversion Enabled by Birefringent Reflective Metasurfaces Chang, C., Zhao, Z., Li, D., Taylor, A. J., Fan, S., Chen, H., IEEE IEEE. 2020
  • PT -symmetric topological edge-gain effect Song, A. Y., Sun, X., Dutt, A., Minkov, M., Wojcik, C., Wang, H., Williamson, I., Orenstein, M., Fan, S., IEEE IEEE. 2020
  • Penetration Depth Engineering in Plasmonic Metafilms for Enhanced Reflection and Confinement Zhao, N., Williamson, I. D., Zhao, Z., Boutami, S., Fan, S., IEEE IEEE. 2020
  • Higher-order topological insulators in synthetic dimensions. Light, science & applications Dutt, A., Minkov, M., Williamson, I. A., Fan, S. 2020; 9: 131

    Abstract

    Conventional topological insulators support boundary states with dimension one lower than that of the bulk system that hosts them, and these states are topologically protected due to quantized bulk dipole moments. Recently, higher-order topological insulators have been proposed as a way of realizing topological states with dimensions two or more lower than that of the bulk due to the quantization of bulk quadrupole or octupole moments. However, all these proposals as well as experimental realizations have been restricted to real-space dimensions. Here, we construct photonic higher-order topological insulators (PHOTIs) in synthetic dimensions. We show the emergence of a quadrupole PHOTI supporting topologically protected corner modes in an array of modulated photonic molecules with a synthetic frequency dimension, where each photonic molecule comprises two coupled rings. By changing the phase difference of the modulation between adjacent coupled photonic molecules, we predict a dynamical topological phase transition in the PHOTI. Furthermore, we show that the concept of synthetic dimensions can be exploited to realize even higher-order multipole moments such as a fourth-order hexadecapole (16-pole) insulator supporting 0D corner modes in a 4D hypercubic synthetic lattice that cannot be realized in real-space lattices.

    View details for DOI 10.1038/s41377-020-0334-8

    View details for PubMedID 32704364

  • Reprogrammable Electro-Optic Nonlinear Activation Functions for Optical Neural Networks IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS Williamson, I. D., Hughes, T. W., Minkov, M., Bartlett, B., Pai, S., Fan, S. 2020; 26 (1)
  • Absence of unidirectionally propagating surface plasmon-polaritons at nonreciprocal metal-dielectric interfaces. Nature communications Buddhiraju, S. n., Shi, Y. n., Song, A. n., Wojcik, C. n., Minkov, M. n., Williamson, I. A., Dutt, A. n., Fan, S. n. 2020; 11 (1): 674

    Abstract

    In the presence of an external magnetic field, the surface plasmon polariton that exists at the metal-dielectric interface is believed to support a unidirectional frequency range near the surface plasmon frequency, where the surface plasmon polariton propagates along one but not the opposite direction. Recent works have pointed to some of the paradoxical consequences of such a unidirectional range, including in particular the violation of the time-bandwidth product constraint that should otherwise apply in general in static systems. Here we show that such a unidirectional frequency range is nonphysical using both a general thermodynamic argument and a detailed calculation based on a nonlocal hydrodynamic Drude model for the metal permittivity. Our calculation reveals that the surface plasmon-polariton at metal-dielectric interfaces remains bidirectional for all frequencies.

    View details for DOI 10.1038/s41467-020-14504-9

    View details for PubMedID 32015328

  • Doubly resonant photonic crystal cavity based on a bound state in the continuum for efficient second harmonic generation Minkov, M., Fan, S., Wang, J., Hodre, R., Clementi, M., Barone, A., Gerace, D., Galli, M., IEEE IEEE. 2020
  • Topological Behaviors in Networks of Time-Multiplexed Optical Resonators Leefmans, C., Dutt, A., Williams, J., Yuan, L., Fan, S., Marandi, A., IEEE IEEE. 2020
  • Recurrent Machine Learning and Computing with Nonlinear Optical Waves Williamson, I. D., Hughes, T. W., Minkov, M., Fan, S., IEEE IEEE. 2020
  • Silicon nitride waveguide as a power delivery component for dielectric laser accelerators Zhao, Z., Tan, S., Urbanek, K., Hughes, T., Lee, Y., Fan, S., Harris, J. S., Byer, R. L., IEEE IEEE. 2020
  • Parallel Fault-Tolerant Programming and Optimization of Photonic Neural Networks Pai, S., Williamson, I. D., Minkov, M., Hughes, T. W., Solgaard, O., Fan, S., Miller, D. B., IEEE IEEE. 2020
  • Broadband Linear-to-Circular Polarization Conversion Enabled by Birefringent Off-Resonance Reflective Metasurfaces. Physical review letters Chang, C. C., Zhao, Z., Li, D., Taylor, A. J., Fan, S., Chen, H. T. 2019; 123 (23): 237401

    Abstract

    Due to the scarcity of circular polarization light sources, linear-to-circular polarization conversion is required to generate circularly polarized light for a variety of applications. Despite significant past efforts, broadband linear-to-circular polarization conversion remains elusive particularly in the terahertz and midinfrared frequency ranges. Here we propose a novel mechanism based on coupled mode theory, and experimentally demonstrate at terahertz frequencies that highly efficient (power conversion efficiency approaching unity) and ultrabroadband (fractional bandwidth up to 80%) linear-to-circular polarization conversion can be accomplished by the judicious design of birefringent metasurfaces. The underlying mechanism operates in the frequency range between well separated resonances, and relies upon the phase response of these resonances away from the resonant frequencies, as well as the balance of the resonant and nonresonant channels. This mechanism is applicable for any operating frequencies from microwave to visible. The present Letter potentially opens a wide range of opportunities in wireless communications, spectroscopy, and emergent quantum materials research where circularly polarized light is desired.

    View details for DOI 10.1103/PhysRevLett.123.237401

    View details for PubMedID 31868454

  • Broadband Linear-to-Circular Polarization Conversion Enabled by Birefringent Off-Resonance Reflective Metasurfaces PHYSICAL REVIEW LETTERS Chang, C., Zhao, Z., Li, D., Taylor, A. J., Fan, S., Chen, H. 2019; 122 (23)
  • Wave physics as an analog recurrent neural network. Science advances Hughes, T. W., Williamson, I. A., Minkov, M., Fan, S. 2019; 5 (12): eaay6946

    Abstract

    Analog machine learning hardware platforms promise to be faster and more energy efficient than their digital counterparts. Wave physics, as found in acoustics and optics, is a natural candidate for building analog processors for time-varying signals. Here, we identify a mapping between the dynamics of wave physics and the computation in recurrent neural networks. This mapping indicates that physical wave systems can be trained to learn complex features in temporal data, using standard training techniques for neural networks. As a demonstration, we show that an inverse-designed inhomogeneous medium can perform vowel classification on raw audio signals as their waveforms scatter and propagate through it, achieving performance comparable to a standard digital implementation of a recurrent neural network. These findings pave the way for a new class of analog machine learning platforms, capable of fast and efficient processing of information in its native domain.

    View details for DOI 10.1126/sciadv.aay6946

    View details for PubMedID 31903420

  • Ultrafast pyroelectric photodetection with on-chip spectral filters. Nature materials Stewart, J. W., Vella, J. H., Li, W., Fan, S., Mikkelsen, M. H. 2019

    Abstract

    Thermal detectors, such as bolometric, pyroelectric and thermoelectric devices, are uniquely capable of sensing incident radiation for any electromagnetic frequency; however, the response times of practical devices are typically on the millisecond scale1-7. By integrating a plasmonic metasurface with an aluminium nitride pyroelectric thin film, we demonstrate spectrally selective, room-temperature pyroelectric detectors from 660-2,000nm with an instrument-limited 1.7ns full width at half maximum and 700ps rise time. Heat generated from light absorption diffuses through the subwavelength absorber into the pyroelectric film producing responsivities up to 0.18VW-1 due to the temperature-dependent spontaneous polarization of the pyroelectric films. Moreover, finite-element simulations reveal the possibility of reaching a 25ps full width at half maximum and 6ps rise time rivalling that of semiconductor photodiodes8. This design approach has the potential to realize large-area, inexpensive gigahertz pyroelectric detectors for wavelength-specific detection from the ultraviolet to short-wave infrared or beyond for, for example, high-speed hyperspectral imaging.

    View details for DOI 10.1038/s41563-019-0538-6

    View details for PubMedID 31768011

  • Generating Light from Darkness JOULE Raman, A. P., Li, W., Fan, S. 2019; 3 (11): 2679–86
  • Relation between photon thermal Hall effect and persistent heat current in nonreciprocal radiative heat transfer PHYSICAL REVIEW B Guo, C., Guo, Y., Fan, S. 2019; 100 (20)
  • Rare Earth Doped Optical Fibers with Multi-section Core. iScience Huang, C., Geng, J., Luo, T., Han, J., Wang, Q., Liang, R., Fan, S., Jiang, S. 2019; 22: 423–29

    Abstract

    The gain bandwidth of a single-mode fiber is limited by the atomic transitions of one rare earth gain element. Here we overcome this long-standing challenge by designing a new single-mode fiber with multi-section core, where each section is doped with different gain element. We theoretically propose and experimentally demonstrate that this configuration provides a gain bandwidth well beyond the capability of conventional design, whereas the inclusion of multiple sections does not compromise single-mode operation or the quality of the transverse modal profile. This new fiber will be beneficial in realizing all fiber laser systems with few-cycle pulse duration or octave tunability.

    View details for DOI 10.1016/j.isci.2019.11.017

    View details for PubMedID 31816529

  • Casimir force between two plasmonic metallic plates from a real frequency perspective JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS Iizuka, H., Fan, S. 2019; 36 (11): 2981–88
  • Forward-Mode Differentiation of Maxwell's Equations ACS PHOTONICS Hughes, T. W., Williamson, I. D., Minkov, M., Fan, S. 2019; 6 (11): 3010–16
  • Nighttime radiative cooling in hot and humid climates OPTICS EXPRESS Dong, M., Chen, N., Zhao, X., Fan, S., Chen, Z. 2019; 27 (22): 31587–98

    Abstract

    Most existing experiments on radiative cooling are conducted in dry climates for better performance. However, many important applications require cooling in hot and humid climates. Here we theoretically analyze the temperature reduction and cooling flux at nighttime with the ambient temperature (Tambient) ranging from 0-40  ∘C and the relative humidity (RH) from 0-100%. Our analysis reveals an interesting crossover: for lower (higher) RH, higher (lower) Tambient results in better cooling. Experimentally, we show that radiative cooling of 5  ∘C below ambient can be achieved even at Tambient = 29  ∘C with RH = 100%.

    View details for DOI 10.1364/OE.27.031587

    View details for Web of Science ID 000492996000041

    View details for PubMedID 31684390

  • Efficient pixel-by-pixel optimization of photonic devices utilizing the Dyson's equation in a Green's function formalism: Part II. Implementation using standard electromagnetic solvers JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS Boutami, S., Fan, S. 2019; 36 (9): 2387–94
  • Near-complete violation of Kirchhoff's law of thermal radiation with a 0.3 T magnetic field OPTICS LETTERS ZHAO, B., Shi, Y., Wang, J., Zha, Z., Zhao, N., Fan, S. 2019; 44 (17): 4203–6

    Abstract

    The capability to overcome Kirchhoff's law of thermal radiation provides new opportunities in energy harvesting and thermal radiation control. Previously, design towards demonstrating such capability requires a magnetic field of 3 T, which is difficult to achieve in practice. In this work, we propose a nanophotonic design that can achieve such capability with a far more modest magnetic field of 0.3 Tesla, a level that can be achieved with permanent magnets. Our design uses guided resonance in low-loss dielectric gratings sitting on a magneto-optical material, which provides significant enhancement on the sensitivity to the external magnetic field.

    View details for DOI 10.1364/OL.44.004203

    View details for Web of Science ID 000483918900029

    View details for PubMedID 31465363

  • Efficient pixel-by-pixel optimization of photonic devices utilizing the Dyson's equation in a Green's function formalism: Part I. Implementation with the method of discrete dipole approximation JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS Boutami, S., Fan, S. 2019; 36 (9): 2378–86
  • Wave optics light-trapping theory: mathematical justification and ultimate limit on enhancement JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS Wang, K., Guo, Y., Fan, S. 2019; 36 (9): 2414–22
  • Doubly resonant chi((2)) nonlinear photonic crystal cavity based on a bound state in the continuum OPTICA Minkov, M., Gerace, D., Fan, S. 2019; 6 (8): 1039–45
  • High-Temperature Polarization-Free III-Nitride Solar Cells with Self-Cooling Effects ACS PHOTONICS Huang, X., Li, W., Fu, H., Li, D., Zhang, C., Chen, H., Fang, Y., Fu, K., DenBaars, S. P., Nakamura, S., Goodnick, S. M., Ning, C., Fan, S., Zhao, Y. 2019; 6 (8): 2096–2103
  • Penetration Depth Reduction with Plasmonic Metafilms ACS PHOTONICS Zhao, N. Z., Williamson, I. D., Zhao, Z., Boutami, S., Fan, S. 2019; 6 (8): 2049–55
  • Accelerating adjoint variable method based photonic optimization with Schur complement domain decomposition OPTICS EXPRESS Zhao, N. Z., Boutami, S., Fan, S. 2019; 27 (15): 20711–19
  • Experimental band structure spectroscopy along a synthetic dimension. Nature communications Dutt, A., Minkov, M., Lin, Q., Yuan, L., Miller, D. A., Fan, S. 2019; 10 (1): 3122

    Abstract

    There has been significant recent interest in synthetic dimensions, where internal degrees of freedom of a particle are coupled to form higher-dimensional lattices in lower-dimensional physical structures. For these systems, the concept of band structure along the synthetic dimension plays a central role in their theoretical description. Here we provide a direct experimental measurement of the band structure along the synthetic dimension. By dynamically modulating a resonator at frequencies commensurate with its mode spacing, we create a periodically driven lattice of coupled modes in the frequency dimension. The strength and range of couplings can be dynamically reconfigured by changing the modulation amplitude and frequency. We show theoretically and demonstrate experimentally that time-resolved transmission measurements of this system provide a direct readout of its band structure. We also realize long-range coupling, gauge potentials and nonreciprocal bands by simply incorporating additional frequency drives, enabling great flexibility in band structure engineering.

    View details for DOI 10.1038/s41467-019-11117-9

    View details for PubMedID 31311928

  • Arbitrary Polarization Conversion with a Photonic Crystal Slab ADVANCED OPTICAL MATERIALS Guo, Y., Xiao, M., Zhou, Y., Fan, S. 2019; 7 (14)
  • Photon Blockade in Weakly Driven Cavity Quantum Electrodynamics Systems with Many Emitters. Physical review letters Trivedi, R., Radulaski, M., Fischer, K. A., Fan, S., Vučković, J. 2019; 122 (24): 243602

    Abstract

    We use the scattering matrix formalism to analyze photon blockade in coherently driven cavity quantum electrodynamics systems with a weak drive. By approximating the weak coherent drive by an input single- and two-photon Fock state, we reduce the computational complexity of the transmission and the two-photon correlation function from exponential to polynomial in the number of emitters. This enables us to easily analyze cavity-based systems containing ∼50 quantum emitters with modest computational resources. Using this approach we study the coherence statistics of photon blockade while increasing the number of emitters for resonant and detuned multiemitter cavity quantum electrodynamics systems-we find that increasing the number of emitters worsens photon blockade in resonant systems, and improves it in detuned systems. We also analyze the impact of inhomogeneous broadening in the emitter frequencies on the photon blockade through this system.

    View details for DOI 10.1103/PhysRevLett.122.243602

    View details for PubMedID 31322381

  • Temperature Regulation in Colored Infrared-Transparent Polyethylene Textiles JOULE Cai, L., Peng, Y., Xu, J., Zhou, C., Zhou, C., Wu, P., Lin, D., Fan, S., Cui, Y. 2019; 3 (6): 1478–86
  • Reconfigurable Photonic Circuit for Controlled Power Delivery to Laser-Driven Accelerators on a Chip PHYSICAL REVIEW APPLIED Hughes, T. W., England, R., Fan, S. 2019; 11 (6)
  • Implications of exceptional points for few-photon transport in waveguide quantum electrodynamics PHYSICAL REVIEW A Xu, S., Fan, S. 2019; 99 (6)
  • Self-sustaining thermophotonic circuits. Proceedings of the National Academy of Sciences of the United States of America Zhao, B., Buddhiraju, S., Santhanam, P., Chen, K., Fan, S. 2019

    Abstract

    Photons represent one of the most important heat carriers. The ability to convert photon heat flow to electricity is therefore of substantial importance for renewable energy applications. However, photon-based systems that convert heat to electricity, including thermophotovoltaic systems where photons are generated from passive thermal emitters, have long been limited by low power density. This limitation persists even with near-field enhancement techniques. Thermophotonic systems, which utilize active photon emitters such as light-emitting diodes, have the potential to significantly further enhance the power density. However, this potential has not been realized in practice, due in part to the fundamental difficulty in thermodynamics of designing a self-sustaining circuit that enables steady-state power generation. Here, we overcome such difficulty by introducing a configuration where the light-emitting diodes are connected in series, and thus multiple photons can be generated from a single injected electron. As a result we propose a self-sustaining thermophotonic circuit where the steady-state power density can exceed thermophotovoltaic systems by many orders of magnitude. This work points to possibilities for constructing heat engines with light as the working medium. The flexibility of controlling the relations between electron and photon flux, as we show in our design, may also be of general importance for optoelectronics-based energy technology.

    View details for DOI 10.1073/pnas.1904938116

    View details for PubMedID 31118287

  • Broadband Optical Switch based on an Achromatic Photonic Gauge Potential in Dynamically Modulated Waveguides PHYSICAL REVIEW APPLIED Williamson, I. D., Fan, S. 2019; 11 (5)
  • Compact dynamic optical isolator based on tandem phase modulators OPTICS LETTERS Lin, Q., Wang, J., Fan, S. 2019; 44 (9): 2240–43

    Abstract

    Non-magnetic dynamic optical isolators, constructed from modulators, provide a complementary metal oxide semiconductor (CMOS)-compatible approach to optical isolation in integrated photonics. The size of these isolators is strongly constrained by both the frequency and strength of optical modulation. Recent developments in modulators have indicated that large modulation strength, with a magnitude refractive index modulation up to unity, may be possible at gigahertz modulation frequency. In this Letter, we show that a previously proposed dynamic isolator design, based on tandem modulators, can be modified to take advantage of the possibility of such large modulation strength. Compared with the previously proposed tandem modulator design, our modification can lead to significant reduction of the device length without the need to increase modulation frequency.

    View details for DOI 10.1364/OL.44.002240

    View details for Web of Science ID 000466351300028

    View details for PubMedID 31042193

  • Experimental demonstration of energy harvesting from the sky using the negative illumination effect of a semiconductor photodiode APPLIED PHYSICS LETTERS Ono, M., Santhanam, P., Li, W., Zhao, B., Fan, S. 2019; 114 (16)

    View details for DOI 10.1063/1.5089783

    View details for Web of Science ID 000466264600002

  • Laterally confined photonic crystal surface emitting laser incorporating monolayer tungsten disulfide NPJ 2D MATERIALS AND APPLICATIONS Ge, X., Minkov, M., Fan, S., Li, X., Zhou, W. 2019; 3
  • Anti-parity-time symmetry in diffusive systems SCIENCE Li, Y., Peng, Y., Han, L., Miri, M., Li, W., Xiao, M., Zhu, X., Zhao, J., Alu, A., Fan, S., Qiu, C. 2019; 364 (6436): 170-+
  • Connection of temporal coupled-mode-theory formalisms for a resonant optical system and its time-reversal conjugate PHYSICAL REVIEW A Zhao, Z., Guo, C., Fan, S. 2019; 99 (3)
  • Photonic Gauge Potential in One Cavity with Synthetic Frequency and Orbital Angular Momentum Dimensions. Physical review letters Yuan, L., Lin, Q., Zhang, A., Xiao, M., Chen, X., Fan, S. 2019; 122 (8): 083903

    Abstract

    We explore a single degenerate optical cavity supporting a synthetic two-dimensional space, which includes the frequency and the orbital angular momentum (OAM) axes of light. We create the effective gauge potential inside this synthetic space and show that the system exhibits topologically protected one-way edge states along the OAM axis at the boundaries of the frequency dimension. In this synthetic space, we present a robust generation and manipulation of entanglement between the frequency and OAM of photons. Our Letter shows that a higher-dimensional synthetic space involving multiple degrees of freedom of light can be achieved in a "zero-dimensional" spatial structure, pointing towards a unique platform to explore topological photonics and to realize potential applications in optical communications and quantum information processing.

    View details for DOI 10.1103/PhysRevLett.122.083903

    View details for PubMedID 30932579

  • Gate-Tunable Near-Field Heat Transfer ACS PHOTONICS Papadakis, G. T., Zhao, B., Buddhiraju, S., Fan, S. 2019; 6 (3): 709–19
  • Scattering of electromagnetic waves by cylinder inside uniaxial hyperbolic medium OPTICS EXPRESS Rituraj, Catrysse, P. B., Fan, S. 2019; 27 (4): 3991–4003
  • Modal approach to optical forces between waveguides as derived by transformation optics formalism OPTICS LETTERS Iizuka, H., Fan, S. 2019; 44 (4): 867–70

    Abstract

    Optical force between two lossless waveguides has been described by two approaches. One approach is the explicit description of the force by the Maxwell stress tensor. Another approach is to describe the modal force in terms of the derivative of the eigenmode frequency with respect to the distance variation. Here, we analytically prove the equivalence of these two approaches for lossless waveguides having arbitrary cross sections through the use of transformation optics formalism. Our derivation is applicable to both pressure and shear forces. We also show that these two approaches are not equivalent in the presence of loss.

    View details for DOI 10.1364/OL.44.000867

    View details for Web of Science ID 000458786800037

    View details for PubMedID 30768007

  • Dynamics for encircling an exceptions point in a nonlinear non-Hermitian system OPTICS LETTERS Wang, H., Assawaworrarit, S., Fan, S. 2019; 44 (3): 638–41

    Abstract

    We study the dynamics near an exceptional point in a nonlinear non-Hermitian system consisting of a pair of resonators. One of the resonators has a linear loss, and the other resonator has a saturable gain. We show that the system dynamics exhibit chiral characteristics. And moreover, unique to the nonlinear system, such dynamics allow one to adiabatically switch between bistable states at the same system parameter. Such bistable switching is potentially interesting in optical memory based on coupled laser systems.

    View details for DOI 10.1364/OL.44.000638

    View details for Web of Science ID 000457292400044

    View details for PubMedID 30702698

  • High Reflection from a One-Dimensional Array of Graphene Nanoribbons ACS PHOTONICS Zhao, N., Zhao, Z., Williamson, I. D., Boutami, S., Zhao, B., Fan, S. 2019; 6 (2): 339–44
  • Simultaneously and Synergistically Harvest Energy from the Sun and Outer Space JOULE Chen, Z., Zhu, L., Li, W., Fan, S. 2019; 3 (1): 101–10
  • Silicon nitride waveguide as a power delivery component for on-chip dielectric laser accelerators OPTICS LETTERS Tan, S., Zhao, Z., Urbanek, K., Hughes, T., Lee, Y., Fan, S., Harris, J. S., Byer, R. L. 2019; 44 (2): 335–38

    Abstract

    We study the weakly guided silicon nitride waveguide as an on-chip power delivery solution for dielectric laser accelerators (DLAs). We focus on the two main limiting factors on the waveguide network for DLAs: the optical damage and nonlinear characteristics. The typical delivered fluence at the onset of optical damage is measured to be ∼0.19  J/cm2 at a 2 μm central wavelength and 250 fs pulse width. This damage fluence is lower than that of the bulk Si3N4 (∼0.65  J/cm2), but higher than that of bulk silicon (∼0.17  J/cm2). We also report the nonlinearity-induced spectrum and phase variance of the output pulse at this pulse duration. We find that a total waveguide length within 3 mm is sufficient to avoid significant self-phase modulation effects when operating slightly below the damage threshold. We also estimate that one SiNx waveguide can power 70 μm silicon dual pillar DLAs from a single side, based on the results from the recent free-space DLA experiment.

    View details for DOI 10.1364/OL.44.000335

    View details for Web of Science ID 000455620100039

    View details for PubMedID 30644894

  • Direction-dependent parity-time phase transition and nonreciprocal amplification with dynamic gain-loss modulation PHYSICAL REVIEW A Song, A. Y., Shi, Y., Lin, Q., Fan, S. 2019; 99 (1)
  • Subwavelength angle-sensing photodetectors inspired by internally coupled ears in small animals Yi, S., Zhou, M., Yu, Z., Fan, P., Behdad, N., Lin, D., Wang, K., Fan, S., Brongersm, M., Panchapakesan, B., Attias, A. J. SPIE-INT SOC OPTICAL ENGINEERING. 2019

    View details for DOI 10.1117/12.2529594

    View details for Web of Science ID 000502134800007

  • Optically pumped 1 mu m low threshold photonic crystal surface emitting lasers grown on GaAs substrate Kalapala, A. K., Yeom, S., Addamane, S. J., Reilly, K. J., Song, A., Gibson, R., Balakrishnan, G., Bedford, R., Fan, S., Zhou, W., IEEE IEEE. 2019
  • Training of Photonic Neural Networks through In Situ Backpropagation Hughes, T. W., Minkov, M., Williamson, I. D., Shi, Y., Fan, S., IEEE IEEE. 2019
  • Adjoint-based inverse design of nonlinear nanophotonic devices Hughes, T. W., Minkov, M., Williamson, I. D., Fan, S., IEEE IEEE. 2019
  • Adjoint-based optimization of active nanophotonic devices Wang, J., Shi, Y., Hughes, T., Zhao, Z., Fan, S., IEEE IEEE. 2019
  • Broadband Switches Using Photonic Aharonov-Bohm Interferometers and Dynamic Modulation Williamson, I. D., Fan, S., IEEE IEEE. 2019
  • Pulse shortening in two coupled rings under amplitude modulations with parity-time symmetry Yuan, L., Lin, Q., Xiao, M., Dutt, A., Fan, S., IEEE IEEE. 2019
  • Optical computing of spatial differentiation without Fourier optics Zhu, T., Lou, Y., Zhou, Y., Zhang, J., Huang, J., Li, Y., Luo, H., Wen, S., Zhu, S., Gong, Q., Ye, H., Qiu, M., Fan, S., Ruan, Z., IEEE IEEE. 2019
  • Scattering of electromagnetic waves by cylinder inside uniaxial hyperbolic medium Rituraj, Catrysse, P. B., Fan, S., Engheta, N., Noginov, M. A., Zheludev, N. I. SPIE-INT SOC OPTICAL ENGINEERING. 2019

    View details for DOI 10.1117/12.2527212

    View details for Web of Science ID 000511108800014

  • Optical Image Processing Using Photonic Crystal Slab Guo, C., Xiao, M., Minkov, M., Shi, Y., Fan, S., Adibi, A., Lin, S. Y., Scherer, A. SPIE-INT SOC OPTICAL ENGINEERING. 2019

    View details for DOI 10.1117/12.2516018

    View details for Web of Science ID 000511111900007

  • High Reflection from a One-Dimensional Array of Graphene Nanoribbons Zhao, N., Zhao, Z., Williamson, I. D., Boutami, S., Zhao, B., Fan, S., IEEE IEEE. 2019
  • Absence of frequency ranges of undirectional propagation in nonreciprocal plasmonics Buddhiraju, S., Shi, Y., Song, A., Wojcik, C., Minkov, M., Williamson, I. D., Dutt, A., Fan, S., IEEE IEEE. 2019
  • Experimental Band Structure Spectroscopy along the Synthetic Dimension Dutt, A., Minkov, M., Lin, Q., Yuan, L., Miller, D. B., Fan, S., IEEE IEEE. 2019
  • Lossless Zero-Index Guided Modes via Bound States in the Continuum Minkov, M., Williamson, I. D., Xiao, M., Fan, S., IEEE IEEE. 2019
  • Design of a tapered slot waveguide dielectric laser accelerator for sub-relativistic electrons Zhao, Z., Hughes, T. W., Tan, S., Deng, H., Sapra, N., England, R., Vuckovic, J., Harris, J. S., Byer, R. L., Fan, S., IEEE IEEE. 2019
  • Thermal meta-device in analogue of zero-index photonics NATURE MATERIALS Li, Y., Zhu, K., Peng, Y., Li, W., Yang, T., Xu, H., Chen, H., Zhu, X., Fan, S., Qiu, C. 2019; 18 (1): 48-+
  • Fano resonance photonic crystal filters and modulators PHOTONIC CRYSTAL METASURFACE OPTOELECTRONICS Zhou, W., Fan, S., Zhou, W., Fan, S. 2019; 100: 149–88
  • Direct Object Recognition Without Line-of-Sight Using Optical Coherence Lei, X., He, L., Tan, Y., Wang, K., Wang, X., Du, Y., Fan, S., Yu, Z., IEEE Comp Soc IEEE. 2019: 11729–38
  • A single photonic cavity with two independent physical synthetic dimensions. Science (New York, N.Y.) Dutt, A. n., Lin, Q. n., Yuan, L. n., Minkov, M. n., Xiao, M. n., Fan, S. n. 2019

    Abstract

    The concept of synthetic dimensions has generated interest in many branches of science ranging from ultracold-atomic physics to photonics, as it provides a versatile platform for realizing effective gauge potentials and topological physics. Previous experiments have augmented the real-space dimensionality by one additional physical synthetic dimension. We endow a single ring resonator with two independent physical synthetic dimensions. Our system consists of a temporally modulated ring resonator with spatial coupling between the clockwise and counterclockwise modes, creating a synthetic Hall ladder along the frequency and pseudospin degrees of freedom for photons propagating in the ring. We observe a wide variety of rich physics, including effective spin-orbit coupling, magnetic fields, spin-momentum locking, a Meissner-to-vortex phase transition, and signatures of topological chiral one-way edge currents, completely in synthetic dimensions. Our experiments demonstrate that higher-dimensional physics can be studied in simple systems by leveraging the concept of multiple simultaneous synthetic dimensions.

    View details for DOI 10.1126/science.aaz3071

    View details for PubMedID 31780626

  • Fano resonance principles in photonic crystal slabs PHOTONIC CRYSTAL METASURFACE OPTOELECTRONICS Zhou, W., Fan, S., Zhou, W., Fan, S. 2019; 100: 1–12
  • Optical image processing using photonic crystal slab PHOTONIC CRYSTAL METASURFACE OPTOELECTRONICS Guo, C., Fan, S., Zhou, W., Fan, S. 2019; 100: 93–114
  • Anti-parity-time symmetry in diffusive systems. Science (New York, N.Y.) Li, Y., Peng, Y., Han, L., Miri, M., Li, W., Xiao, M., Zhu, X., Zhao, J., Alo, A., Fan, S., Qiu, C. 2019; 364 (6436): 170–73

    Abstract

    Various concepts related to parity-time symmetry, including anti-parity-time symmetry, have found broad applications in wave physics. Wave systems are fundamentally described by Hermitian operators, whereas their unusual properties are introduced by incorporation of gain and loss. We propose that the related physics need not be restricted to wave dynamics, and we consider systems described by diffusive dynamics. We study the heat transfer in two countermoving media and show that this system exhibits anti-parity-time symmetry. The spontaneous symmetry breaking results in a phase transition from motionless temperature profiles, despite the mechanical motion of the background, to moving temperature profiles. Our results extend the concepts of parity-time symmetry beyond wave physics and may offer opportunities to manipulate heat and mass transport.

    View details for PubMedID 30975886

  • Electronically programmable photonic molecule NATURE PHOTONICS Zhang, M., Wang, C., Hu, Y., Shams-Ansari, A., Ren, T., Fan, S., Loncar, M. 2019; 13 (1): 36-+
  • Experimental Demonstration of Dynamical Input Isolation in Nonadiabatically Modulated Photonic Cavities ACS PHOTONICS Dutt, A., Minkov, M., Lin, Q., Yuan, L., Miller, D. B., Fan, S. 2019; 6 (1): 162–69
  • Zero-Index Bound States in the Continuum. Physical review letters Minkov, M., Williamson, I. A., Xiao, M., Fan, S. 2018; 121 (26): 263901

    Abstract

    Metamaterials with an effective zero refractive index associated with their electromagnetic response are sought for a number of applications in communications and nonlinear optics. A promising way that this can be achieved in all-dielectric photonic crystals is through the design of a Dirac cone at zero Bloch wave vector in the photonic band structure. In the optical frequency range, the natural way to implement this design is through the use of a photonic crystal slab. In the existing implementation, however, the zero-index photonic modes also radiate strongly into the environment due to intrinsic symmetry properties. This has resulted in large losses in recent experimental realizations of this zero-index paradigm. Here, we propose a photonic crystal slab with zero-index modes which are also symmetry-protected bound states in the continuum. Our approach thus eliminates the associated radiation loss. This could enable, for the first time, large-scale integration of zero-index materials in photonic devices.

    View details for DOI 10.1103/PhysRevLett.121.263901

    View details for PubMedID 30636117

  • Thermal meta-device in analogue of zero-index photonics. Nature materials Li, Y., Zhu, K., Peng, Y., Li, W., Yang, T., Xu, H., Chen, H., Zhu, X., Fan, S., Qiu, C. 2018

    Abstract

    Inspired by the developments in photonic metamaterials, the concept of thermal metamaterials has promised new avenues for manipulating the flow of heat. In photonics, the existence of natural materials with both positive and negative permittivities has enabled the creation of metamaterials with a very wide range of effective parameters. In contrast, in conductive heat transfer, the available range of thermal conductivities in natural materials is far narrower, strongly restricting the effective parameters of thermal metamaterials and limiting possible applications in extreme environments. Here, we identify a rigorous correspondence between zero index in Maxwell's equations and infinite thermal conductivity in Fourier's law. We also propose a conductive system with an integrated convective element that creates an extreme effective thermal conductivity, and hence by correspondence a thermal analogue of photonic near-zero-index metamaterials, a class of metamaterials with crucial importance in controlling light. Synergizing the general properties of zero-index metamaterials and the specific diffusive nature of thermal conduction, we theoretically and experimentally demonstrate a thermal zero-index cloak. In contrast with conventional thermal cloaks, this meta-device can operate in a highly conductive background and the cloaked object preserves great sensitivity to external temperature changes. Our work demonstrates a thermal metamaterial which greatly enhances the capability for molding the flow of heat.

    View details for PubMedID 30510270

  • Adjoint Method and Inverse Design for Nonlinear Nanophotonic Devices ACS PHOTONICS Hughes, T. W., Minkov, M., Williamson, I. D., Fan, S. 2018; 5 (12): 4781–87
  • Subwavelength angle-sensing photodetectors inspired by directional hearing in small animals (vol 13, pg 1143, 2018) NATURE NANOTECHNOLOGY Yi, S., Zhou, M., Yu, Z., Fan, P., Behdad, N., Lin, D., Wang, K., Fan, S., Brongersma, M. 2018; 13 (12): 1191
  • Subwavelength angle-sensing photodetectors inspired by directional hearing in small animals NATURE NANOTECHNOLOGY Yi, S., Zhou, M., Yu, Z., Fan, P., Behdad, N., Lin, D., Wang, K., Fan, S., Brongersma, M. 2018; 13 (12): 1143-+
  • Synthetic dimension in photonics OPTICA Yuan, L., Lin, Q., Xiao, M., Fan, S. 2018; 5 (11): 1396–1405
  • Author Correction: Subwavelength angle-sensing photodetectors inspired by directional hearing in small animals. Nature nanotechnology Yi, S., Zhou, M., Yu, Z., Fan, P., Behdad, N., Lin, D., Wang, K. X., Fan, S., Brongersma, M. 2018

    Abstract

    In the version of this Letter originally published, Zongfu Yu was mistakenly not noted as being a corresponding author; this has now been corrected in all versions of the Letter.

    View details for PubMedID 30443033

  • Three-Dimensional Chiral Lattice Fermion in Floquet Systems. Physical review letters Sun, X. Q., Xiao, M., Bzdušek, T., Zhang, S. C., Fan, S. 2018; 121 (19): 196401

    Abstract

    We show that the Nielsen-Ninomiya no-go theorem still holds on a Floquet lattice: there is an equal number of right-handed and left-handed Weyl points in a three-dimensional Floquet lattice. However, in the adiabatic limit, where the time evolution of the low-energy subspace is decoupled from the high-energy subspace, we show that the bulk dynamics in the low-energy subspace can be described by Floquet bands with extra left- or right-handed Weyl points, despite the no-go theorem. Assuming adiabatic evolution of two bands, we show that the difference of the number of right-handed and left-handed Weyl points equals twice the winding number of the adiabatic Floquet operator over the Brillouin zone. Based on these findings, we propose a realization of purely left- or right-handed Weyl particles on a 3D lattice using a Hamiltonian obtained through dimensional reduction of a four-dimensional quantum Hall system. We argue that the breakdown of the adiabatic approximation on the surface facilitates unusual closed orbits of wave packets in an applied magnetic field, which traverse alternatively through the low-energy and high-energy sector of the spectrum.

    View details for DOI 10.1103/PhysRevLett.121.196401

    View details for PubMedID 30468621

  • Three-Dimensional Chiral Lattice Fermion in Floquet Systems PHYSICAL REVIEW LETTERS Sun, X., Xiao, M., Bzdusek, T., Zhang, S., Fan, S. 2018; 121 (19)
  • Nonreciprocal Optical Dissipation Based on Direction-Dependent Rabi Splitting IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS Shi, Y., Lin, Q., Minkov, M., Fan, S. 2018; 24 (6)
  • Impact of objective bandwidth and frequency sampling density on search landscape structure and search performance in design optimization of optical structures JOURNAL OF OPTICS Verweij, S., Fan, S. 2018; 20 (11)
  • Nonreciprocal Photonics Without Magneto-Optics IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS Fan, S., Shi, Y., Lin, Q. 2018; 17 (11): 1948–52
  • Generate tensor network state by sequential single-photon scattering in waveguide QED systems APL PHOTONICS Xu, S., Fan, S. 2018; 3 (11)

    View details for DOI 10.1063/1.5044248

    View details for Web of Science ID 000451738400011

  • Subwavelength angle-sensing photodetectors inspired by directional hearing in small animals. Nature nanotechnology Yi, S., Zhou, M., Yu, Z., Fan, P., Behdad, N., Lin, D., Wang, K. X., Fan, S., Brongersma, M. 2018

    Abstract

    Sensing the direction of sounds gives animals clear evolutionary advantage. For large animals, with an ear-to-ear spacing that exceeds audible sound wavelengths, directional sensing is simply accomplished by recognizing the intensity and time differences of a wave impinging on its two ears1. Recent research suggests that in smaller, subwavelength animals, angle sensing can instead rely on a coherent coupling of soundwaves between the two ears2-4. Inspired by this natural design, here we show a subwavelength photodetection pixel that can measure both the intensity and incident angle of light. It relies on an electrical isolation and optical coupling of two closely spaced Si nanowires that support optical Mie resonances5-7. When these resonators scatter light into the same free-space optical modes, a non-Hermitian coupling results that affords highly sensitive angle determination. By straightforward photocurrent measurements, we can independently quantify the stored optical energy in each nanowire and relate the difference in the stored energy between the wires to the incident angle of a light wave. We exploit this effect to fabricate a subwavelength angle-sensitive pixel with angular sensitivity, deltatheta=0.32°.

    View details for PubMedID 30374161

  • Few-photon scattering and emission from low-dimensional quantum systems PHYSICAL REVIEW B Trivedi, R., Fischer, K., Xu, S., Fan, S., Vuckovic, J. 2018; 98 (14)
  • Photonic thermal management of coloured objects. Nature communications Li, W., Shi, Y., Chen, Z., Fan, S. 2018; 9 (1): 4240

    Abstract

    The colours of outdoor structures, such as automobiles, buildings and clothing, are typically chosen for functional or aesthetic reasons. With a chosen colour, however, one must control the radiative thermal load for heating or cooling purposes. Here we provide a comprehensive calculation of the tunable range of radiative thermal load for all colours. The range exceeds 680Wm-2 for all colours, and can be as high as 866Wm-2, resulting from effects of metamerism, infrared solar absorption and radiative cooling. We experimentally demonstrate that two photonic structures with the same pink colour can have their temperatures differ by 47.6°C under sunlight. These structures are over 20°C either cooler or hotter than a commercial paint with a comparable colour. Furthermore, the hotter pink structure is 10°C hotter than a commercial black paint. These results elucidate the fundamental potentials of photonic thermal management for coloured objects.

    View details for PubMedID 30315155

  • Photonic thermal management of coloured objects NATURE COMMUNICATIONS Li, W., Shi, Y., Chen, Z., Fan, S. 2018; 9
  • Unidirectional light transport in dynamically modulated waveguides PHYSICAL REVIEW APPLIED Minkov, M., Fan, S. 2018; 10 (4)
  • Enhanced high-harmonic generation from an all-dielectric metasurface NATURE PHYSICS Liu, H., Guo, C., Vampa, G., Zhang, J., Sarmiento, T., Xiao, M., Bucksbaum, P. H., Vuckovic, J., Fan, S., Reis, D. A. 2018; 14 (10): 1006-+
  • A three-dimensional photonic topological insulator using a two-dimensional ring resonator lattice with a synthetic frequency dimension SCIENCE ADVANCES Lin, Q., Sun, X., Xiao, M., Zhang, S., Fan, S. 2018; 4 (10)
  • Isotropic wavevector domain image filters by a photonic crystal slab device JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION Guo, C., Xiao, M., Minkov, M., Shi, Y., Fan, S. 2018; 35 (10): 1685–91
  • A three-dimensional photonic topological insulator using a two-dimensional ring resonator lattice with a synthetic frequency dimension. Science advances Lin, Q., Sun, X., Xiao, M., Zhang, S., Fan, S. 2018; 4 (10): eaat2774

    Abstract

    In the development of topological photonics, achieving three-dimensional topological insulators is of notable interest since it enables the exploration of new topological physics with photons and promises novel photonic devices that are robust against disorders in three dimensions. Previous theoretical proposals toward three-dimensional topological insulators use complex geometries that are challenging to implement. On the basis of the concept of synthetic dimension, we show that a two-dimensional array of ring resonators, which was previously demonstrated to exhibit a two-dimensional topological insulator phase, automatically becomes a three-dimensional topological insulator when the frequency dimension is taken into account. Moreover, by modulating a few of the resonators, a screw dislocation along the frequency axis can be created, which provides robust one-way transport of photons along the frequency axis. Demonstrating the physics of screw dislocation in a topological system has been a substantial challenge in solid-state systems. Our work indicates that the physics of three-dimensional topological insulators can be explored in standard integrated photonic platforms, leading to opportunities for novel devices that control the frequency of light.

    View details for PubMedID 30345351

  • MESH: A free electromagnetic solver for far-field and near-field radiative heat transfer for layered periodic structures COMPUTER PHYSICS COMMUNICATIONS Chen, K., Zhao, B., Fan, S. 2018; 231: 163–72
  • Design of a tapered slot waveguide dielectric laser accelerator for sub-relativistic electrons OPTICS EXPRESS Zhao, Z., Hughes, T. W., Tan, S., Deng, H., Sapra, N., England, R., Vuckovic, J., Harris, J. S., Byer, R. L., Fan, S. 2018; 26 (18): 22801–15

    Abstract

    We propose a dielectric laser accelerator design based on a tapered slot waveguide structure for sub-relativistic electron acceleration. This tapering scheme allows for straightforward tuning of the phase velocity of the accelerating field along the propagation direction, which is necessary for maintaining synchronization with electrons as their velocities increase. Furthermore, the non-resonant nature of this design allows for better tolerance to experimental errors. We also introduce a method to design this continuously tapered structure based on the eikonal approximation, and give a working example based on realistic experimental parameters.

    View details for DOI 10.1364/OE.26.022801

    View details for Web of Science ID 000443431400037

    View details for PubMedID 30184935

  • Self-adaptive radiative cooling based on phase change materials OPTICS EXPRESS Ono, M., Chen, K., Li, W., Fan, S. 2018; 26 (18): A777–A787

    Abstract

    With the ability of harvesting the coldness of universe as a thermodynamic resource, radiative cooling technology is important for a broad range of applications such as passive building cooling, refrigeration, and renewable energy harvesting. However, all existing radiative cooling technologies utilize static structures, which lack the ability of self-adaptive tuning based on demand. Here we present the concept of self-adaptive radiative cooling based on phase change materials such as vanadium dioxide. We design a photonic structure that can adaptively turn 'on' and 'off' radiative cooling, depending the ambient temperature, without any extra energy input for switching. Our results here lead to new functionalities of radiative cooling and can potentially be used in a wide range of applications for the thermal managements of buildings, vehicles and textiles.

    View details for DOI 10.1364/OE.26.00A777

    View details for Web of Science ID 000443431400007

    View details for PubMedID 30184837

  • Spectrally Selective Nanocomposite Textile for Outdoor Personal Cooling ADVANCED MATERIALS Cai, L., Song, A. Y., Li, W., Hsu, P., Lin, D., Catrysse, P. B., Liu, Y., Peng, Y., Chen, J., Wang, H., Xu, J., Yang, A., Fan, S., Cui, Y. 2018; 30 (35)
  • Polarization control with dielectric helix metasurfaces and arrays OPTICS EXPRESS Karakasoglu, I., Xiao, M., Fan, S. 2018; 26 (17): 21664–74

    Abstract

    Using band structure analysis and reflectance spectrum simulations, we show that dielectric helices exhibit strong circular dichroism and have polarization stop gaps for light propagating perpendicular to the helices, despite the lack of helical symmetry along this direction. We apply perturbation theory to quantitatively explain these effects. We also demonstrate that even for a single layer of dielectric helices similar phenomena exist. As a result, the helix array can operate as a dielectric chiral mirror. This dielectric chiral mirror can completely reflect normally incident light with one circular polarization (right- or left-handed as determined by the handedness of the helices) without changing the polarization's handedness while allowing light with the opposite circular polarization to be entirely transmitted.

    View details for DOI 10.1364/OE.26.021664

    View details for Web of Science ID 000442136200024

    View details for PubMedID 30130869

  • Pulse shortening in an actively mode-locked laser with parity-time symmetry APL PHOTONICS Yuan, L., Lin, Q., Xiao, M., Dutt, A., Fan, S. 2018; 3 (8)

    View details for DOI 10.1063/1.5039375

    View details for Web of Science ID 000443758300001

  • Near-Field Thermophotonic Systems for Low-Grade Waste-Heat Recovery NANO LETTERS Zhao, B., Santhanam, P., Chen, K., Buddhiraju, S., Fan, S. 2018; 18 (8): 5224–30

    Abstract

    Low-grade waste heat contains an enormous amount of exergy that can be recovered for renewable-energy generation. Current solid-state techniques for recovering low-grade waste heat, such as thermoelectric generators and thermophotovoltaics, however, are limited by low conversion efficiencies or power densities. In this work, we propose a solid-state near-field thermophotonic system. The system consists of a light-emitting diode (LED) on the hot side and a photovoltaic (PV) cell on the cold side. Part of the generated power by the PV cell is used to positively bias the LED. When operating in the near-field regime, the system can have power density and conversion efficiency significantly exceeding the performance of current solid-state approaches for low-grade waste-heat recovery. For example, when the gap spacing is 10 nm and the hot side and cold side are, respectively, 600 and 300 K, we show that the generated electric power density and thermal-to-electrical conversion efficiency can reach 9.6 W/cm2 and 9.8%, respectively, significantly outperforming the current record-setting thermoelectric generators. We identify the alignment of the band gaps of the LED and the PV cell, the appropriate choice of thickness of the LED and PV cell to mitigate the effect of non-radiative recombination, and the use of highly reflective back mirrors as key factors that affect the performance of the system. Our work points to the significant potential of photonic systems for the recovery of low-grade waste heat.

    View details for DOI 10.1021/acs.nanolett.8b02184

    View details for Web of Science ID 000441478300084

    View details for PubMedID 30016115

  • Relation between absorption and emission directivities for dipoles coupled with optical antennas PHYSICAL REVIEW A Zhao, Z., Shi, Y., Chen, K., Fan, S. 2018; 98 (1)
  • First-principles simulation of photonic crystal surface-emitting lasers using rigorous coupled wave analysis APPLIED PHYSICS LETTERS Song, A. Y., Kalapala, A., Zhou, W., Fan, S. 2018; 113 (4)

    View details for DOI 10.1063/1.5045486

    View details for Web of Science ID 000440046600006

  • Training of photonic neural networks through in situ backpropagation and gradient measurement OPTICA Hughes, T. W., Minkov, M., Shi, Y., Fan, S. 2018; 5 (7): 864–71
  • Spectrally Selective Nanocomposite Textile for Outdoor Personal Cooling. Advanced materials (Deerfield Beach, Fla.) Cai, L., Song, A. Y., Li, W., Hsu, P., Lin, D., Catrysse, P. B., Liu, Y., Peng, Y., Chen, J., Wang, H., Xu, J., Yang, A., Fan, S., Cui, Y. 2018: e1802152

    Abstract

    Outdoor heat stress poses a serious public health threat and curtails industrial labor supply and productivity, thus adversely impacting the wellness and economy of the entire society. With climate change, there will be more intense and frequent heat waves that further present a grand challenge for sustainability. However, an efficient and economical method that can provide localized outdoor cooling of the human body without intensive energy input is lacking. Here, a novel spectrally selective nanocomposite textile for radiative outdoor cooling using zinc oxide nanoparticle-embedded polyethylene is demonstrated. By reflecting more than 90% solar irradiance and selectively transmitting out human body thermal radiation, this textile can enable simulated skin to avoid overheating by 5-13 °C compared to normal textile like cotton under peak daylight condition. Owing to its superior passive cooling capability and compatibility with large-scale production, this radiative outdoor cooling textile is promising to widely benefit the sustainability of society in many aspects spanning from health to economy.

    View details for PubMedID 30015999

  • Accelerating convergence of iterative solution of finite difference frequency domain problems via schur complement domain decomposition OPTICS EXPRESS Zhao, N., Verweij, S., Shin, W., Fan, S. 2018; 26 (13): 16925–39
  • Effective electric-field force for a photon in a synthetic frequency lattice created in a waveguide modulator PHYSICAL REVIEW A Qin, C., Yuan, L., Wang, B., Fan, S., Lu, P. 2018; 97 (6)
  • Nanophotonic control of thermal radiation for energy applications [Invited] OPTICS EXPRESS Li, W., Fan, S. 2018; 26 (12): 15995–6021
  • Size Scaling of Photonic Crystal Surface Emitting Lasers on Silicon Substrates IEEE PHOTONICS JOURNAL Liu, S., Zhao, D., Ge, X., Reuterskiold-Hedlund, C., Hammar, M., Fan, S., Ma, Z., Zhou, W. 2018; 10 (3)
  • On-Chip Laser-Power Delivery System for Dielectric Laser Accelerators PHYSICAL REVIEW APPLIED Hughes, T. W., Tan, S., Zhao, Z., Sapra, N. V., Leedle, K. J., Deng, H., Miao, Y., Black, D. S., Solgaard, O., Harris, J. S., Vuckovic, J., Byer, R. L., Fan, S., England, R., Lee, Y., Qi, M. 2018; 9 (5)
  • Broadband Control of Topological Nodes in Electromagnetic Fields PHYSICAL REVIEW LETTERS Song, A. Y., Catrysse, P. B., Fan, S. 2018; 120 (19): 193903

    Abstract

    We study topological nodes (phase singularities) in electromagnetic wave interactions with structures. We show that, when the nodes exist, it is possible to bind certain nodes to a specific plane in the structure by a combination of mirror and time-reversal symmetry. Such binding does not rely on any resonances in the structure. As a result, the nodes persist on the plane over a wide wavelength range. As an implication of such broadband binding, we demonstrate that the topological nodes can be used for hiding of metallic objects over a broad wavelength range.

    View details for PubMedID 29799227

  • Electroluminescent refrigeration by ultra-efficient GaAs light-emitting diodes JOURNAL OF APPLIED PHYSICS Xiao, T., Chen, K., Santhanam, P., Fan, S., Yablonovitch, E. 2018; 123 (17)

    View details for DOI 10.1063/1.5019764

    View details for Web of Science ID 000431651600004

  • Thermodynamic limits of energy harvesting from outgoing thermal radiation PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Buddhiraju, S., Santhanam, P., Fan, S. 2018; 115 (16): E3609–E3615

    Abstract

    We derive the thermodynamic limits of harvesting power from the outgoing thermal radiation from the ambient to the cold outer space. The derivations are based on a duality relation between thermal engines that harvest solar radiation and those that harvest outgoing thermal radiation. In particular, we derive the ultimate limit for harvesting outgoing thermal radiation, which is analogous to the Landsberg limit for solar energy harvesting, and show that the ultimate limit far exceeds what was previously thought to be possible. As an extension of our work, we also derive the ultimate limit of efficiency of thermophotovoltaic systems.

    View details for PubMedID 29610347

  • Low index contrast heterostructure photonic crystal cavities with high quality factors and vertical radiation coupling APPLIED PHYSICS LETTERS Ge, X., Minkov, M., Fan, S., Li, X., Zhou, W. 2018; 112 (14)

    View details for DOI 10.1063/1.5026433

    View details for Web of Science ID 000429344100005

  • Response to "Comment on 'High-performance near-field electroluminescent refrigeration device consisting of a GaAs light emitting diode and a Si photovoltaic cell'" [J. Appl. Phys. 122, 143104 (2017)] JOURNAL OF APPLIED PHYSICS Chen, K., Xiao, T., Santhanam, P., Yablonovitch, E., Fan, S. 2018; 123 (11)

    View details for DOI 10.1063/1.5023511

    View details for Web of Science ID 000428070900055

  • Photonic crystal slab Laplace operator for image differentiation OPTICA Guo, C., Xiao, M., Minkov, M., Shi, Y., Fan, S. 2018; 5 (3): 251–56
  • Synthetic space with arbitrary dimensions in a few rings undergoing dynamic modulation PHYSICAL REVIEW B Yuan, L., Xiao, M., Lin, Q., Fan, S. 2018; 97 (10)
  • Theory of many-body radiative heat transfer without the constraint of reciprocity PHYSICAL REVIEW B Zhu, L., Guo, Y., Fan, S. 2018; 97 (9)
  • Metamaterials for radiative sky cooling NATIONAL SCIENCE REVIEW Fan, S., Raman, A. 2018; 5 (2): 132–33

    View details for DOI 10.1093/nsr/nwy012

    View details for Web of Science ID 000428637600006

  • Optimization of Multilayer Optical Films with a Memetic Algorithm and Mixed Integer Programming ACS PHOTONICS Shi, Y., Li, W., Raman, A., Fan, S. 2018; 5 (3): 684–91
  • Enhancing Mo:BiVO4 Solar Water Splitting with Patterned Au Nanospheres by Plasmon-Induced Energy Transfer ADVANCED ENERGY MATERIALS Kim, J., Shi, X., Jeong, M., Park, J., Han, H., Kim, S., Guo, Y., Heinz, T. F., Fan, S., Lee, C., Park, J., Zheng, X. 2018; 8 (5)
  • Effects of non-Hermitian perturbations on Weyl Hamiltonians with arbitrary topological charges PHYSICAL REVIEW B Cerjan, A., Xiao, M., Yuan, L., Fan, S. 2018; 97 (7)
  • Localization and time-reversal of light through dynamic modulation PHYSICAL REVIEW B Minkov, M., Fan, S. 2018; 97 (6)
  • Significant Enhancement of Near-Field Electromagnetic Heat Transfer in a Multilayer Structure through Multiple Surface-States Coupling PHYSICAL REVIEW LETTERS Iizuka, H., Fan, S. 2018; 120 (6): 063901

    Abstract

    We show that near-field electromagnetic heat transfer between multilayer thermal bodies can be significantly enhanced by the contributions of surface states at multiple surfaces. As a demonstration, we show that when one of the materials forming the multilayer structure is described by the Drude model, and the other one is a vacuum, at the same gap spacing the resulting heat transfer can be up to 40 times higher as compared to that between two semi-infinite materials described by the same Drude model. Moreover, this system can exhibit a nonmonotonic dependency in its heat transfer coefficient as a function of the middle gap spacing. The enhancement effect in the system persists for realistic materials.

    View details for PubMedID 29481235

  • Adjoint-based optimization of active nanophotonic devices OPTICS EXPRESS Wang, J., Shi, Y., Hughes, T., Zhao, Z., Fan, S. 2018; 26 (3): 3236–48

    Abstract

    We show that the adjoint variable method can be combined with the multi-frequency finite-difference frequency-domain method for efficient sensitivity calculations, enabling the systematic optimization of active nanophotonic devices. As a proof of principle demonstration, we have optimized a dynamic isolator structure in two-dimensions, resulting in the reduction of the length of the modulated regions by a factor of two, while retaining good performance in the isolation ratio and insertion loss.

    View details for DOI 10.1364/OE.26.003236

    View details for Web of Science ID 000425365900097

    View details for PubMedID 29401854

  • Nanoporous polyethylene microfibres for large-scale radiative cooling fabric NATURE SUSTAINABILITY Peng, Y., Chen, J., Song, A. Y., Catrysse, P. B., Hsu, P., Cai, L., Liu, B., Zhu, Y., Zhou, G., Wu, D. S., Lee, H., Fan, S., Cui, Y. 2018; 1 (2): 105–12
  • Anti-Hermitian photodetector facilitating efficient subwavelength photon sorting NATURE COMMUNICATIONS Kim, S., Kang, J., Mutlu, M., Park, J., Park, W., Goodson, K. E., Sinclair, R., Fan, S., Kik, P. G., Brongersma, M. L. 2018; 9: 316

    Abstract

    The ability to split an incident light beam into separate wavelength bands is central to a diverse set of optical applications, including imaging, biosensing, communication, photocatalysis, and photovoltaics. Entirely new opportunities are currently emerging with the recently demonstrated possibility to spectrally split light at a subwavelength scale with optical antennas. Unfortunately, such small structures offer limited spectral control and are hard to exploit in optoelectronic devices. Here, we overcome both challenges and demonstrate how within a single-layer metafilm one can laterally sort photons of different wavelengths below the free-space diffraction limit and extract a useful photocurrent. This chipscale demonstration of anti-Hermitian coupling between resonant photodetector elements also facilitates near-unity photon-sorting efficiencies, near-unity absorption, and a narrow spectral response (∼ 30 nm) for the different wavelength channels. This work opens up entirely new design paradigms for image sensors and energy harvesting systems in which the active elements both sort and detect photons.

    View details for PubMedID 29358626

  • Nonreciprocal optical manipulation using dynamic modulation Shi, Y., Minkov, M., Fan, S., Lin, Q., IEEE IEEE. 2018
  • Analysis of an Anti-reflecting Nanowire Transparent Electrode for Solar Cells Zhao, Z., Wang, K., Fan, S., IEEE IEEE. 2018
  • Near-field thermo-photovoltaic platform Bhatt, G. R., Roberts, S., St-Gelais, R., Lin, T., Mohanty, A., Zhao, B., Hartmann, J., Fan, S., Lipson, M., IEEE IEEE. 2018
  • A Large Area Monolayer WS2 Laser Based on Surface-Emitting Heterostructure Photonic Crystal Cavities Ge, X., Minkov, M., Li, X., Fan, S., Zhou, W., IEEE IEEE. 2018
  • A Photonic Crystal Slab Laplace Differentiator Guo, C., Xiao, M., Minkov, M., Shi, Y., Fan, S., IEEE IEEE. 2018
  • Effects of non-Hermitian perturbations on Weyl Hamiltonians with arbitrary topological charges Cerjan, A., Xiao, M., Yuan, L., Fan, S., IEEE IEEE. 2018
  • Photonic Chern insulator through homogenization of an array of particles Xiao, M., Fan, S., IEEE IEEE. 2018
  • Memetic Algorithm Optimization of Thin-film Photonic Structures for Thermal and Energy Applications Shi, Y., Li, W., Raman, A., Fan, S., IEEE IEEE. 2018
  • Localization, Time-reversal, and Unidirectional Guiding of Light Pulses Using Dynamic Modulation Minkov, M., Fan, S., IEEE IEEE. 2018
  • Enhanced Solid-State High-Harmonic Generation from a Silicon Metasurface Liu, H., Guo, C., Vampa, G., Zhang, J., Sarmiento, T., Xiao, M., Bucksbaum, P. H., Vuckovic, J., Fan, S., Reis, D. A., IEEE IEEE. 2018
  • Spontaneous and Stimulated Emission from Quantum Optical Systems Trivedi, R., Fischer, K., Xu, S., Fan, S., Vuckovic, J., IEEE IEEE. 2018
  • Broadband Control of Topological Nodes in Electromagnetic Fields Song, A. Y., Catrysse, P. B., Fan, S., IEEE IEEE. 2018
  • Achieving Topological Photonics in a Synthetic Space with Dynamically Modulated Ring Resonators Yuan, L., Xiao, M., Lin, Q., Fan, S., IEEE IEEE. 2018
  • Complete photonic bandgaps in supercell photonic crystals Cerjan, A., Fan, S., IEEE IEEE. 2018
  • Scaling towards Efficient Monolayer WS2 Photonic Crystal Lasers Ge, X., Minkov, M., Li, X., Fan, S., Zhou, W., IEEE IEEE. 2018: 21–22
  • Non-Hermitian and topological electromagnetics: synthetic dimensions, and robust wireless power transfer Fan, S., IEEE IEEE. 2018: 19
  • Direct Measurement of Directional Emission from Monolayer WS2 Laser with Heterostructure Photonic Crystal Cavities Ge, X., Minkov, M., Fan, S., Li, X., Zhou, W., Winzer, P., Tsang, H. K., Capmany, J., Yao, J., Fontaine, N., Dutta, N. IEEE. 2018
  • Design of Light-Emitting Diodes and Photovoltaic Cells for Electroluminescent Refrigeration Xiao, T., Chen, K., Santhanam, P., Fan, S., Yablonovitch, E., IEEE IEEE. 2018: 1868–U1094
  • Decoupled textures for broadband absorption enhancement beyond Lambertian light trapping limit in thin-film silicon-based solar cells Vismara, R., Linssen, D. P., Wang, K. X., Fan, S., Isabella, O., Zeman, M., IEEE IEEE. 2018: 3455–59
  • Room Temperature Photonic Crystal Surface Emitting Laser with Synthesized Monolayer Tungsten Disulfide Ge, X., Minkov, M., Choudhury, T., Chubarov, M., Fan, S., Redwing, J., Li, X., Zhou, W., IEEE IEEE. 2018: 167–68
  • Complete photonic band gaps in supercell photonic crystals PHYSICAL REVIEW A Cerjan, A., Fan, S. 2017; 96 (5)
  • High-performance near-field thermophotovoltaics for waste heat recovery NANO ENERGY Zhao, B., Chen, K., Buddhiraju, S., Bhatt, G., Lipson, M., Fan, S. 2017; 41: 344–50
  • A dual-mode textile for human body radiative heating and cooling SCIENCE ADVANCES Hsu, P., Liu, C., Song, A. Y., Zhang, Z., Peng, Y., Xie, J., Liu, K., Wu, C., Catrysse, P. B., Cai, L., Zhai, S., Majumdar, A., Fan, S., Cui, Y. 2017; 3 (11): e1700895

    Abstract

    Maintaining human body temperature is one of the most basic needs for living, which often consumes a huge amount of energy to keep the ambient temperature constant. To expand the ambient temperature range while maintaining human thermal comfort, the concept of personal thermal management has been recently demonstrated in heating and cooling textiles separately through human body infrared radiation control. Realizing these two opposite functions within the same textile would represent an exciting scientific challenge and a significant technological advancement. We demonstrate a dual-mode textile that can perform both passive radiative heating and cooling using the same piece of textile without any energy input. The dual-mode textile is composed of a bilayer emitter embedded inside an infrared-transparent nanoporous polyethylene (nanoPE) layer. We demonstrate that the asymmetrical characteristics of both emissivity and nanoPE thickness can result in two different heat transfer coefficients and achieve heating when the low-emissivity layer is facing outside and cooling by wearing the textile inside out when the high-emissivity layer is facing outside. This can expand the thermal comfort zone by 6.5°C. Numerical fitting of the data further predicts 14.7°C of comfort zone expansion for dual-mode textiles with large emissivity contrast.

    View details for PubMedID 29296678

  • Creating anyons from photons using a nonlinear resonator lattice subject to dynamic modulation PHYSICAL REVIEW A Yuan, L., Xiao, M., Xu, S., Fan, S. 2017; 96 (4)
  • High-performance near-field electroluminescent refrigeration device consisting of a GaAs light emitting diode and a Si photovoltaic cell JOURNAL OF APPLIED PHYSICS Chen, K., Xiao, T. P., Santhanam, P., Yablonovitch, E., Fan, S. 2017; 122 (14)

    View details for DOI 10.1063/1.5007712

    View details for Web of Science ID 000413038500004

  • Thermal Photonics and Energy Applications JOULE Fan, S. 2017; 1 (2): 264–73
  • Exergy in near-field electromagnetic heat transfer JOURNAL OF APPLIED PHYSICS Iizuka, H., Fan, S. 2017; 122 (12)

    View details for DOI 10.1063/1.5004662

    View details for Web of Science ID 000412099600024

  • Photonic Chern insulator through homogenization of an array of particles PHYSICAL REVIEW B Xiao, M., Fan, S. 2017; 96 (10)
  • Warming up human body by nanoporous metallized polyethylene textile NATURE COMMUNICATIONS Cai, L., Song, A. Y., Wu, P., Hsu, P., Peng, Y., Chen, J., Liu, C., Catrysse, P. B., Liu, Y., Yang, A., Zhou, C., Zhou, C., Fan, S., Cui, Y. 2017; 8: 496

    Abstract

    Space heating accounts for the largest energy end-use of buildings that imposes significant burden on the society. The energy wasted for heating the empty space of the entire building can be saved by passively heating the immediate environment around the human body. Here, we demonstrate a nanophotonic structure textile with tailored infrared (IR) property for passive personal heating using nanoporous metallized polyethylene. By constructing an IR-reflective layer on an IR-transparent layer with embedded nanopores, the nanoporous metallized polyethylene textile achieves a minimal IR emissivity (10.1%) on the outer surface that effectively suppresses heat radiation loss without sacrificing wearing comfort. This enables 7.1 °C decrease of the set-point compared to normal textile, greatly outperforming other radiative heating textiles by more than 3 °C. This large set-point expansion can save more than 35% of building heating energy in a cost-effective way, and ultimately contribute to the relief of global energy and climate issues.Energy wasted for heating the empty space of the entire building can be saved by passively heating the immediate environment around the human body. Here, the authors show a nanophotonic structure textile with tailored infrared property for passive personal heating using nanoporous metallized polyethylene.

    View details for PubMedID 28928427

  • Sub-ambient non-evaporative fluid cooling with the sky NATURE ENERGY Goldstein, E. A., Raman, A. P., Fan, S. 2017; 2 (9)
  • Unidirectional reflectionless light propagation at exceptional points NANOPHOTONICS Huang, Y., Shen, Y., Min, C., Fan, S., Veronis, G. 2017; 6 (5): 977-996
  • Electrodeposited high strength, thermally stable spectrally selective rhenium nickel inverse opals NANOSCALE Zhang, R., Cohen, J., Fan, S., Braun, P. V. 2017; 9 (31): 11187–94

    Abstract

    Rhenium-Nickel (RexNi100-x) based 3D metallic inverse opals (IOs) were realized via colloidal crystal templated electrodeposition from an aqueous electrolyte. By varying the electrodeposition parameters, x could be varied from 0 to 88. Under reducing conditions, the rhenium-rich IOs were structurally stable to temperatures of at least 1000 °C for 5 h and for at least 12 h after coating with a thin layer of Al2O3. This demonstrated level of thermal stability is significantly improved compared to previously reported electrodeposited refractory inverse opals with similar characteristic dimensions. A strong frequency dependence in the optical reflection, which ranged from ∼5% around 1.5 μm to ∼65% around 5 μm, is predicted by simulations and experimentally observed, indicating the potential of this structure as a high temperature spectrally selective optical absorber/emitter. The elastic modulus of the ReNi IO structure is ∼35 GPa and the hardness is ∼0.8 GPa. Both these properties are much higher than those of Ni inverse opals and other periodically porous materials with similar characteristic pore dimensions. We suggest this work provides a promising approach for thermally stable mesostructured materials for high temperature catalyst supports, refractory photonics and mechanical applications including high temperature filtration, and high temperature actuators.

    View details for DOI 10.1039/c7nr03567e

    View details for Web of Science ID 000407336600024

    View details for PubMedID 28749496

  • Theory of solar cell light trapping through a nonequilibrium Green's function formulation of Maxwell's equations PHYSICAL REVIEW B Buddhiraju, S., Fan, S. 2017; 96 (3)
  • Objective-trait-bias metaheuristics for design optimization of optical structures JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS Verweij, S., Fan, S. 2017; 34 (7): 1551-1559
  • Exact solution to the steady-state dynamics of a periodically modulated resonator APL PHOTONICS Minkov, M., Shi, Y., Fan, S. 2017; 2 (7)

    View details for DOI 10.1063/1.4985381

    View details for Web of Science ID 000406761000003

  • Optical Circulation and Isolation Based on Indirect Photonic Transitions of Guided Resonance Modes ACS PHOTONICS Shi, Y., Han, S., Fan, S. 2017; 4 (7): 1639–45
  • Near-field heat transfer between graphene/hBN multilayers PHYSICAL REVIEW B Zhao, B., Guizal, B., Zhang, Z. M., Fan, S., Antezza, M. 2017; 95 (24)
  • Method for computationally efficient design of dielectric laser accelerator structures OPTICS EXPRESS Hughes, T., Veronis, G., Wootton, K. P., England, R., Fan, S. 2017; 25 (13): 15414–27

    Abstract

    Dielectric microstructures have generated much interest in recent years as a means of accelerating charged particles when powered by solid state lasers. The acceleration gradient (or particle energy gain per unit length) is an important figure of merit. To design structures with high acceleration gradients, we explore the adjoint variable method, a highly efficient technique used to compute the sensitivity of an objective with respect to a large number of parameters. With this formalism, the sensitivity of the acceleration gradient of a dielectric structure with respect to its entire spatial permittivity distribution is calculated by the use of only two full-field electromagnetic simulations, the original and 'adjoint'. The adjoint simulation corresponds physically to the reciprocal situation of a point charge moving through the accelerator gap and radiating. Using this formalism, we perform numerical optimizations aimed at maximizing acceleration gradients, which generate fabricable structures of greatly improved performance in comparison to previously examined geometries.

    View details for DOI 10.1364/OE.25.015414

    View details for Web of Science ID 000404189800133

    View details for PubMedID 28788967

  • Robust wireless power transfer using a nonlinear parity-time-symmetric circuit NATURE Assawaworrarit, S., Yu, X., Fan, S. 2017; 546 (7658): 387-+

    Abstract

    Considerable progress in wireless power transfer has been made in the realm of non-radiative transfer, which employs magnetic-field coupling in the near field. A combination of circuit resonance and impedance transformation is often used to help to achieve efficient transfer of power over a predetermined distance of about the size of the resonators. The development of non-radiative wireless power transfer has paved the way towards real-world applications such as wireless powering of implantable medical devices and wireless charging of stationary electric vehicles. However, it remains a fundamental challenge to create a wireless power transfer system in which the transfer efficiency is robust against the variation of operating conditions. Here we propose theoretically and demonstrate experimentally that a parity-time-symmetric circuit incorporating a nonlinear gain saturation element provides robust wireless power transfer. Our results show that the transfer efficiency remains near unity over a distance variation of approximately one metre, without the need for any tuning. This is in contrast with conventional methods where high transfer efficiency can only be maintained by constantly tuning the frequency or the internal coupling parameters as the transfer distance or the relative orientation of the source and receiver units is varied. The use of a nonlinear parity-time-symmetric circuit should enable robust wireless power transfer to moving devices or vehicles.

    View details for PubMedID 28617463

  • Generalized cluster decomposition principle illustrated in waveguide quantum electrodynamics PHYSICAL REVIEW A Xu, S., Fan, S. 2017; 95 (6)
  • Plasmonic computing of spatial differentiation NATURE COMMUNICATIONS Zhu, T., Zhou, Y., Lou, Y., Ye, H., Qiu, M., Ruan, Z., Fan, S. 2017; 8

    Abstract

    Optical analog computing offers high-throughput low-power-consumption operation for specialized computational tasks. Traditionally, optical analog computing in the spatial domain uses a bulky system of lenses and filters. Recent developments in metamaterials enable the miniaturization of such computing elements down to a subwavelength scale. However, the required metamaterial consists of a complex array of meta-atoms, and direct demonstration of image processing is challenging. Here, we show that the interference effects associated with surface plasmon excitations at a single metal-dielectric interface can perform spatial differentiation. And we experimentally demonstrate edge detection of an image without any Fourier lens. This work points to a simple yet powerful mechanism for optical analog computing at the nanoscale.

    View details for DOI 10.1038/ncomms15391

    View details for Web of Science ID 000401628400001

    View details for PubMedID 28524882

  • Non-reciprocal geometric phase in nonlinear frequency conversion OPTICS LETTERS Wang, K., Shi, Y., Solntsev, A. S., Fan, S., Sukhorukov, A. A., Neshev, D. N. 2017; 42 (10): 1990-1993

    Abstract

    We describe analytically and numerically the geometric phase arising from nonlinear frequency conversion and show that such a phase can be made non-reciprocal by momentum-dependent photonic transition. Such non-reciprocity is immune to the shortcomings imposed by dynamic reciprocity in Kerr and Kerr-like devices. We propose a simple and practical implementation, requiring only a single waveguide and one pump, while the geometric phase is controllable by the pump and promises robustness against fabrication errors.

    View details for DOI 10.1364/OL.42.001990

    View details for Web of Science ID 000401424900031

    View details for PubMedID 28504731

  • Universal modal radiation laws for all thermal emitters PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Miller, D. A., Zhu, L., Fan, S. 2017; 114 (17): 4336-4341

    Abstract

    We derive four laws relating the absorptivity and emissivity of thermal emitters. Unlike the original Kirchhoff radiation law derivations, these derivations include diffraction, and so are valid also for small objects, and can also cover nonreciprocal objects. The proofs exploit two recent approaches. First, we express all fields in terms of the mode-converter basis sets of beams; these sets, which can be uniquely established for any linear optical object, give orthogonal input beams that are coupled one-by-one to orthogonal output beams. Second, we consider thought experiments using universal linear optical machines, which allow us to couple appropriate beams and black bodies. Two of these laws can be regarded as rigorous extensions of previously known laws: One gives a modal version of a radiation law for reciprocal objects-the absorptivity of any input beam equals the emissivity into the "backward" (i.e., phase-conjugated) version of that beam; another gives the overall equality of the sums of the emissivities and the absorptivities for any object, including nonreciprocal ones. The other two laws, valid for reciprocal and nonreciprocal objects, are quite different from previous relations. One shows universal equivalence of the absorptivity of each mode-converter input beam and the emissivity into its corresponding scattered output beam. The other gives unexpected equivalences of absorptivity and emissivity for broad classes of beams. Additionally, we prove these orthogonal mode-converter sets of input and output beams are the ones that maximize absorptivities and emissivities, respectively, giving these beams surprising additional physical meaning.

    View details for DOI 10.1073/pnas.1701606114

    View details for Web of Science ID 000399995600040

    View details for PubMedID 28396436

  • A Comprehensive Photonic Approach for Solar Cell Cooling ACS PHOTONICS Li, W., Shi, Y., Chen, K., Zhu, L., Fan, S. 2017; 4 (4): 774-782
  • Analysis of an anti-reflecting nanowire transparent electrode for solar cells JOURNAL OF APPLIED PHYSICS Zhao, Z., Wang, K. X., Fan, S. 2017; 121 (11)

    View details for DOI 10.1063/1.4978769

    View details for Web of Science ID 000397421400009

  • Planar, Ultrathin, Subwavelength Spectral Light Separator for Efficient, Wide-Angle Spectral Imaging ACS PHOTONICS Buyukalp, Y., Catrysse, P. B., Shin, W., Fan, S. 2017; 4 (3): 525-535
  • Synthetic gauge potential and effective magnetic field in a Raman medium undergoing molecular modulation PHYSICAL REVIEW A Yuan, L., Wang, D., Fan, S. 2017; 95 (3)
  • Daytime Radiative Cooling Using Near-Black Infrared Emitters ACS PHOTONICS Kou, J., Jurado, Z., Chen, Z., Fan, S., Minnich, A. J. 2017; 4 (3): 626-630
  • Invited Article: Acousto-optic finite-difference frequency- domain algorithm for first-principles simulations of on-chip acousto-optic devices APL PHOTONICS Shi, Y., Cerjan, A., Fan, S. 2017; 2 (2)

    View details for DOI 10.1063/1.4975002

    View details for Web of Science ID 000395386300001

  • Subwavelength Angle Sensing Photodetector Yi, S., Zhou, M., Yu, Z., Fan, P., Lin, D., Fan, S., Brongersma, M., IEEE IEEE. 2017
  • Frequency-axis light transport and topological effects in dynamic photonic structures Yuan, L., Shi, Y., Fan, S., Adibi, A., Lin, S. Y., Scherer, A. SPIE-INT SOC OPTICAL ENGINEERING. 2017

    View details for DOI 10.1117/12.2257705

    View details for Web of Science ID 000399924900014

  • Efficient electroluminescent cooling with a light-emitting diode coupled to a photovoltaic cell (Conference Presentation) Xiao, T. P., Chen, K., Santhanam, P., Fan, S., Yablonovitch, E., Epstein, R. I., Seletskiy, D. V., SheikBahae, M. SPIE-INT SOC OPTICAL ENGINEERING. 2017

    View details for DOI 10.1117/12.2252631

    View details for Web of Science ID 000404886900004

  • Systematic Thermalphotovoltaic Solar Cell Optimization Lyu, Z., Xue, M., Chen, J., Jia, J., Fan, S., Harris, J., IEEE IEEE. 2017: 2732-2735
  • Electro-Luminescent Refrigeration Enabled by Highly Efficient Photovoltaics Xiao, T., Chen, K., Santhanam, P., Fan, S., Yablonovitch, E., IEEE IEEE. 2017: 2185-+
  • Achieving Arbitrary Control over Pairs of Polarization States Using Complex Birefringent Metamaterials. Physical review letters Cerjan, A. n., Fan, S. n. 2017; 118 (25): 253902

    Abstract

    We demonstrate that the key to realizing arbitrary control over pairs of polarization states of light, i.e., transforming an arbitrarily polarized pair of input states to an arbitrarily polarized pair of output states, is the ability to generate pairs of states with orthogonal polarizations from nonorthogonal pairs of initial states. Then, we develop a new class of non-Hermitian metamaterials, termed complex birefringent metamaterials, which are able to do exactly this. Such materials could facilitate the detection of small polarization changes in scattering experiments as well as enable new polarization multiplexing schemes in communications networks.

    View details for PubMedID 28696764

  • Semiconductor-based Multilayer Selective Solar Absorber for Unconcentrated Solar Thermal Energy Conversion. Scientific reports Thomas, N. H., Chen, Z. n., Fan, S. n., Minnich, A. J. 2017; 7 (1): 5362

    Abstract

    Solar thermal energy conversion has attracted substantial renewed interest due to its applications in industrial heating, air conditioning, and electricity generation. Achieving stagnation temperatures exceeding 200 °C, pertinent to these technologies, with unconcentrated sunlight requires spectrally selective absorbers with exceptionally low emissivity in the thermal wavelength range and high visible absorptivity for the solar spectrum. In this Communication, we report a semiconductor-based multilayer selective absorber that exploits the sharp drop in optical absorption at the bandgap energy to achieve a measured absorptance of 76% at solar wavelengths and a low emittance of approximately 5% at thermal wavelengths. In field tests, we obtain a peak temperature of 225 °C, comparable to that achieved with state-of-the-art selective surfaces. With straightforward optimization to improve solar absorption, our work shows the potential for unconcentrated solar thermal systems to reach stagnation temperatures exceeding 300 °C, thereby eliminating the need for solar concentrators for mid-temperature solar applications such as supplying process heat.

    View details for PubMedID 28706230

  • Topologically Protected Complete Polarization Conversion. Physical review letters Guo, Y. n., Xiao, M. n., Fan, S. n. 2017; 119 (16): 167401

    Abstract

    We consider the process of conversion between linear polarizations as light is reflected from a photonic crystal slab. We observe that, over a wide range of frequencies, complete polarization conversion can be found at isolated wave vectors. Moreover, such an effect is topological: the complex reflection coefficients have a nonzero winding number in the wave vector space. We also show that bound states in continuum in this system have their wave vectors lying on the critical coupling curve that defines the condition for complete polarization conversion. Our work points to the use of topological photonics concepts for the control of polarization, and suggests the exploration of topological properties of scattering matrices as a route towards creating robust optical devices.

    View details for PubMedID 29099196

  • Enhancing Near-Field Radiative Heat Transfer with Si-based Metasurfaces. Physical review letters Fernández-Hurtado, V. n., García-Vidal, F. J., Fan, S. n., Cuevas, J. C. 2017; 118 (20): 203901

    Abstract

    We demonstrate in this work that the use of metasurfaces provides a viable strategy to largely tune and enhance near-field radiative heat transfer between extended structures. In particular, using a rigorous coupled wave analysis, we predict that Si-based metasurfaces featuring two-dimensional periodic arrays of holes can exhibit a room-temperature near-field radiative heat conductance much larger than any unstructured material to date. We show that this enhancement, which takes place in a broad range of separations, relies on the possibility to largely tune the properties of the surface plasmon polaritons that dominate the radiative heat transfer in the near-field regime.

    View details for PubMedID 28581797

  • Enhanced Light Emission from MoS2 in Heterostructure Photonic Crystal Cavities Ge, X., Minkov, M., Chowdhury, F., Fan, S., Li, X., Zhou, W., IEEE Photon Soc IEEE. 2017: 461–62
  • Passive Cooling of Solar Cells with a Comprehensive Photonic Approach Li, W., Shi, Y., Chen, K., Zhu, L., Fan, S., IEEE IEEE. 2017: 847–50
  • A Multi-frequency Finite-difference Frequency-domain Algorithm for Active Nanophotonic Device Simulations Shi, Y., Shin, W., Fan, S., IEEE IEEE. 2017
  • Lateral Size Scaling of Photonic Crystal Surface-Emitting Lasers on Si Liu, S., Zhao, D., Yang, H., Reuterskiold-Hedlund, C., Hammar, M., Fan, S., Ma, Z., Zhou, W., IEEE IEEE. 2017
  • Eigenvalue dynamics in the presence of non-uniform gain and loss Cerjan, A., Fan, S., IEEE IEEE. 2017
  • Theory of few-photon quantum scattering in nanophotonic structures Xu, S., Fan, S., Shahriar, S. M., Scheuer, J. SPIE-INT SOC OPTICAL ENGINEERING. 2017

    View details for DOI 10.1117/12.2261178

    View details for Web of Science ID 000404881800010

  • Photonic Weyl Point in a 2D Resonator Array with a Synthetic Frequency Dimension Lin, Q., Xiao, M., Yuan, L., Fan, S., IEEE IEEE. 2017
  • Hot Carrier-Based Near-Field Thermophotovoltaic Energy Conversion. ACS nano St-Gelais, R. n., Bhatt, G. R., Zhu, L. n., Fan, S. n., Lipson, M. n. 2017; 11 (3): 3001–9

    Abstract

    Near-field thermophotovoltaics (NFTPV) is a promising approach for direct conversion of heat to electrical power. This technology relies on the drastic enhancement of radiative heat transfer (compared to conventional blackbody radiation) that occurs when objects at different temperatures are brought to deep subwavelength distances (typically <100 nm) from each other. Achieving such radiative heat transfer between a hot object and a photovoltaic (PV) cell could allow direct conversion of heat to electricity with a greater efficiency than using current solid-state technologies (e.g., thermoelectric generators). One of the main challenges in the development of this technology, however, is its incompatibility with conventional silicon PV cells. Thermal radiation is weak at frequencies larger than the ∼1.1 eV bandgap of silicon, such that PV cells with lower excitation energies (typically 0.4-0.6 eV) are required for NFTPV. Using low bandgap III-V semiconductors to circumvent this limitation, as proposed in most theoretical works, is challenging and therefore has never been achieved experimentally. In this work, we show that hot carrier PV cells based on Schottky junctions between silicon and metallic films could provide an attractive solution for achieving high efficiency NFTPV electricity generation. Hot carrier science is currently an important field of research and several approaches are investigated for increasing the quantum efficiency (QE) of hot carrier generation beyond conventional Fowler model predictions. If the Fowler limit can indeed be overcome, we show that hot carrier-based NFTPV systems-after optimization of their thermal radiation spectrum-could allow electricity generation with up to 10-30% conversion efficiencies and 10-500 W/cm2 generated power densities (at 900-1500 K temperatures). We also discuss how the unique properties of thermal radiation in the extreme near-field are especially well suited for investigating recently proposed approaches for high QE hot carrier junctions. We therefore expect our work to be of interest for the field of hot carrier science and-by relying solely on conventional thin film materials-to provide a path for the experimental demonstration of NFTPV energy conversion.

    View details for PubMedID 28287714

  • Narrowband thermal emission from a uniform tungsten surface critically coupled with a photonic crystal guided resonance OPTICS EXPRESS Guo, Y., Fan, S. 2016; 24 (26): 29896-29907

    Abstract

    We numerically demonstrate narrowband thermal emission with unity emissivity peak in the near-infrared range by critically coupling a flat tungsten surface with guided resonances of a dielectric photonic crystal slab. The tungsten surface is separated from the photonic crystal slab by a vacuum gap. The structure possesses significant tunability for both the center frequency and the linewidth of the thermal emission band. Moreover, the tungsten surface, being un-structured, should exhibit enhanced thermal stability at elevated temperature as compared to tungsten nanostructures.

    View details for DOI 10.1364/OE.24.029896

    View details for Web of Science ID 000390809100062

    View details for PubMedID 28059374

  • Nonequilibrium Casimir Force with a Nonzero Chemical Potential for Photons PHYSICAL REVIEW LETTERS Chen, K., Fan, S. 2016; 117 (26)

    Abstract

    We introduce a new class of nonequilibrium Casimir forces, where the deviation from equilibrium is achieved through the use of a nonzero chemical potential of photons. Such a force can be observed when two semiconductors are brought in close proximity to each other, and when at least one of the semiconductors is subject to an external voltage. By exact numerical calculations of a sphere-plate configuration, we show that in the total force the non-equilibrium component can dominate over its equilibrium counterpart with a relatively modest external voltage, even when the sphere-plate separation is in the nanoscale. As a result, repulsion can be achieved at the nanoscale even with a relatively modest applied voltage. The results here point to a pathway that can significantly advance the quest for observing and harnessing nonequilibrium Casimir forces in solid-state systems.

    View details for DOI 10.1103/PhysRevLett.117.267401

    View details for Web of Science ID 000390301300004

    View details for PubMedID 28059546

  • Effects of non-uniform distributions of gain and loss in photonic crystals NEW JOURNAL OF PHYSICS Cerjan, A., Fan, S. 2016; 18
  • Photonic Weyl point in a two-dimensional resonator lattice with a synthetic frequency dimension NATURE COMMUNICATIONS Lin, Q., Xiao, M., Yuan, L., Fan, S. 2016; 7

    Abstract

    Weyl points, as a signature of 3D topological states, have been extensively studied in condensed matter systems. Recently, the physics of Weyl points has also been explored in electromagnetic structures such as photonic crystals and metamaterials. These structures typically have complex three-dimensional geometries, which limits the potential for exploring Weyl point physics in on-chip integrated systems. Here we show that Weyl point physics emerges in a system of two-dimensional arrays of resonators undergoing dynamic modulation of refractive index. In addition, the phase of modulation can be controlled to explore Weyl points under different symmetries. Furthermore, unlike static structures, in this system the non-trivial topology of the Weyl point manifests in terms of surface state arcs in the synthetic space that exhibit one-way frequency conversion. Our system therefore provides a versatile platform to explore and exploit Weyl point physics on chip.

    View details for DOI 10.1038/ncomms13731

    View details for Web of Science ID 000390283700001

    View details for PubMedID 27976714

    View details for PubMedCentralID PMC5172232

  • Radiative cooling to deep sub-freezing temperatures through a 24-h day-night cycle NATURE COMMUNICATIONS Chen, Z., Zhu, L., Raman, A., Fan, S. 2016; 7

    Abstract

    Radiative cooling technology utilizes the atmospheric transparency window (8-13 μm) to passively dissipate heat from Earth into outer space (3 K). This technology has attracted broad interests from both fundamental sciences and real world applications, ranging from passive building cooling, renewable energy harvesting and passive refrigeration in arid regions. However, the temperature reduction experimentally demonstrated, thus far, has been relatively modest. Here we theoretically show that ultra-large temperature reduction for as much as 60 °C from ambient is achievable by using a selective thermal emitter and by eliminating parasitic thermal load, and experimentally demonstrate a temperature reduction that far exceeds previous works. In a populous area at sea level, we have achieved an average temperature reduction of 37 °C from the ambient air temperature through a 24-h day-night cycle, with a maximal reduction of 42 °C that occurs when the experimental set-up enclosing the emitter is exposed to peak solar irradiance.

    View details for DOI 10.1038/ncomms13729

    View details for Web of Science ID 000389627000001

    View details for PubMedID 27959339

    View details for PubMedCentralID PMC5159822

  • Understanding search behavior via search landscape analysis in design optimization of optical structures JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS Verweij, S., Fan, S. 2016; 33 (12): 2457-2471
  • Photonic Structure Textile Design for Localized Thermal Cooling Based on a Fiber Blending Scheme ACS PHOTONICS Catrysse, P. B., Song, A. Y., Fan, S. 2016; 3 (12): 2420-2426
  • Temporal coupled mode theory linking to surface-wave dispersion relations in near-field electromagnetic heat transfer JOURNAL OF APPLIED PHYSICS Iizuka, H., Fan, S. 2016; 120 (19)

    View details for DOI 10.1063/1.4967832

    View details for Web of Science ID 000388958200013

  • Multi-frequency finite-difference frequency-domain algorithm for active nanophotonic device simulations OPTICA Shi, Y., Shin, W., Fan, S. 2016; 3 (11): 1256-1259
  • Time reversal of a wave packet with temporal modulation of gauge potential PHYSICAL REVIEW B Yuan, L., Xiao, M., Fan, S. 2016; 94 (14)
  • Fano interference in two-photon transport PHYSICAL REVIEW A Xu, S., Fan, S. 2016; 94 (4)
  • Eigenvalue dynamics in the presence of nonuniform gain and loss PHYSICAL REVIEW A Cerjan, A., Fan, S. 2016; 94 (3)
  • Persistent Directional Current at Equilibrium in Nonreciprocal Many-Body Near Field Electromagnetic Heat Transfer PHYSICAL REVIEW LETTERS Zhu, L., Fan, S. 2016; 117 (13)

    Abstract

    We consider the consequence of nonreciprocity in near-field heat transfer by studying systems consisting of magneto-optical nanoparticles. We demonstrate that, in thermal equilibrium, a nonreciprocal many-body system in heat transfer can support a persistent directional heat current, without violating the second law of thermodynamics. Such a persistent directional heat current cannot occur in reciprocal systems, and can only arise in many-body systems in heat transfer. The use of nonreciprocity therefore points to a new regime of near-field heat transfer for the control of heat flow in the nanoscale.

    View details for DOI 10.1103/PhysRevLett.117.134303

    View details for Web of Science ID 000383852100004

    View details for PubMedID 27715122

  • Bloch oscillation and unidirectional translation of frequency in a dynamically modulated ring resonator OPTICA Yuan, L., Fan, S. 2016; 3 (9): 1014-1018
  • Radiative human body cooling by nanoporous polyethylene textile SCIENCE Hsu, P., Song, A. Y., Catrysse, P. B., Liu, C., Peng, Y., Xie, J., Fan, S., Cui, Y. 2016; 353 (6303): 1019-1023

    Abstract

    Thermal management through personal heating and cooling is a strategy by which to expand indoor temperature setpoint range for large energy saving. We show that nanoporous polyethylene (nanoPE) is transparent to mid-infrared human body radiation but opaque to visible light because of the pore size distribution (50 to 1000 nanometers). We processed the material to develop a textile that promotes effective radiative cooling while still having sufficient air permeability, water-wicking rate, and mechanical strength for wearability. We developed a device to simulate skin temperature that shows temperatures 2.7° and 2.0°C lower when covered with nanoPE cloth and with processed nanoPE cloth, respectively, than when covered with cotton. Our processed nanoPE is an effective and scalable textile for personal thermal management.

    View details for DOI 10.1126/science.aaf5471

    View details for PubMedID 27701110

  • Highly tunable refractive index visible-light metasurface from block copolymer self-assembly NATURE COMMUNICATIONS Kim, J. Y., Kim, H., Kim, B. H., Chang, T., Lim, J., Jin, H. M., Mun, J. H., Choi, Y. J., Chung, K., Shin, J., Fan, S., Kim, S. O. 2016; 7

    Abstract

    The refractive index of natural transparent materials is limited to 2-3 throughout the visible wavelength range. Wider controllability of the refractive index is desired for novel optical applications such as nanoimaging and integrated photonics. We report that metamaterials consisting of period and symmetry-tunable self-assembled nanopatterns can provide a controllable refractive index medium for a broad wavelength range, including the visible region. Our approach exploits the independent control of permeability and permittivity with nanoscale objects smaller than the skin depth. The precise manipulation of the interobject distance in block copolymer nanopatterns via pattern shrinkage increased the effective refractive index up to 5.10. The effective refractive index remains above 3.0 over more than 1,000 nm wavelength bandwidth. Spatially graded and anisotropic refractive indices are also obtained with the design of transitional and rotational symmetry modification.

    View details for DOI 10.1038/ncomms12911

    View details for PubMedID 27683077

  • Roadmap on optical metamaterials JOURNAL OF OPTICS Urbas, A. M., Jacob, Z., Dal Negro, L., Engheta, N., Boardman, A. D., Egan, P., Khanikaev, A. B., Menon, V., Ferrera, M., Kinsey, N., Devault, C., Kim, J., Shalaev, V., Boltasseva, A., Valentine, J., Pfeiffer, C., Grbic, A., Narimanov, E., Zhu, L., Fan, S., Alu, A., Poutrina, E., Litchinitser, N. M., Noginov, M. A., MacDonald, K. F., Plum, E., Liu, X., Nealey, P. F., Kagan, C. R., Murray, C. B., Pawlak, D. A., Smolyaninov, I. I., Smolyaninova, V. N., Chanda, D. 2016; 18 (9)
  • Plasmonic Circuit Theory for Multiresonant Light Funneling to a Single Spatial Hot Spot NANO LETTERS Hughes, T. W., Fan, S. 2016; 16 (9): 5764-5769

    Abstract

    We present a theoretical framework, based on plasmonic circuit models, for generating a multiresonant field intensity enhancement spectrum at a single "hot spot" in a plasmonic device. We introduce a circuit model, consisting of an array of coupled LC resonators, that directs current asymmetrically in the array, and we show that this circuit can funnel energy efficiently from each resonance to a single element. We implement the circuit model in a plasmonic nanostructure consisting of a series of metal bars of differing length, with nearest neighbor metal bars strongly coupled electromagnetically through air gaps. The resulting nanostructure resonantly traps different wavelengths of incident light in separate gap regions, yet it funnels the energy of different resonances to a common location, which is consistent with our circuit model. Our work is important for a number of applications of plasmonic nanoantennas in spectroscopy, such as in single-molecule fluorescence spectroscopy or Raman spectroscopy.

    View details for DOI 10.1021/acs.nanolett.6b02474

    View details for Web of Science ID 000383412100066

    View details for PubMedID 27518827

  • Slanted gold mushroom array: a switchable bi/tridirectional surface plasmon polariton splitter. Nanoscale Shen, Y., Fang, G., Cerjan, A., Chi, Z., Fan, S., Jin, C. 2016; 8 (34): 15505-15513

    Abstract

    Surface plasmon polaritons (SPPs) show great promise in providing an ultracompact platform for integrated photonic circuits. However, challenges remain in easily and efficiently coupling light into and subsequently routing SPPs. Here, we theoretically propose and experimentally demonstrate a switchable bi/tridirectional beam splitter which can simultaneously perform both tasks. The photonic device consists of a periodic array of slanted gold 'mushrooms' composed of angled dielectric pillars with gold caps extruding from a periodic array of perforations in a gold film. The unidirectional coupling results from the interference of the in-plane guided modes scattered by a pair of dislocated gold gratings, while the output channel is determined by the polarization of the incident beam. This device, in combination with dynamic polarization modulation techniques, has the potential to serve as a router or switch in plasmonic integrated circuits.

    View details for DOI 10.1039/c6nr03488h

    View details for PubMedID 27523083

  • Near-Field Enhanced Negative Luminescent Refrigeration PHYSICAL REVIEW APPLIED Chen, K., Santhanam, P., Fan, S. 2016; 6 (2)
  • Hyperbolic Weyl Point in Reciprocal Chiral Metamaterials. Physical review letters Xiao, M., Lin, Q., Fan, S. 2016; 117 (5): 057401-?

    Abstract

    We report the existence of Weyl points in a class of noncentral symmetric metamaterials, which has time reversal symmetry, but does not have inversion symmetry due to chiral coupling between electric and magnetic fields. This class of metamaterial exhibits either type-I or type-II Weyl points depending on its nonlocal response. We also provide a physical realization of such metamaterial consisting of an array of metal wires in the shape of elliptical helices which exhibits type-II Weyl points.

    View details for DOI 10.1103/PhysRevLett.117.057401

    View details for PubMedID 27517792

  • High-Performance Ultrathin BiVO4 Photoanode on Textured Polydimethylsiloxane Substrates for Solar Water Splitting ACS ENERGY LETTERS Zhao, J., Guo, Y., Cai, L., Li, H., Wang, K. X., Cho, I. S., Lee, C. H., Fan, S., Zheng, X. 2016; 1 (1): 68-75
  • Roadmap on optical energy conversion JOURNAL OF OPTICS Boriskina, S. V., Green, M. A., Catchpole, K., Yablonovitch, E., Beard, M. C., Okada, Y., Lany, S., Gershon, T., Zakutayev, A., Tahersima, M. H., Sorger, V. J., Naughton, M. J., Kempa, K., Dagenais, M., Yao, Y., Xu, L., Sheng, X., Bronstein, N. D., Rogers, J. A., Alivisatos, A. P., Nuzzo, R. G., Gordon, J. M., Wu, D. M., Wisser, M. D., Salleo, A., Dionne, J., Bermel, P., Greffet, J., Celanovic, I., Soljacic, M., Manor, A., Rotschild, C., Raman, A., Zhu, L., Fan, S., Chen, G. 2016; 18 (7)
  • Near-field radiative heat transfer between parallel structures in the deep subwavelength regime NATURE NANOTECHNOLOGY St-Gelais, R., Zhu, L., Fan, S., Lipson, M. 2016; 11 (6): 515-?

    Abstract

    Thermal radiation between parallel objects separated by deep subwavelength distances and subject to large thermal gradients (>100 K) can reach very high magnitudes, while being concentrated on a narrow frequency distribution. These unique characteristics could enable breakthrough technologies for thermal transport control and electricity generation (for example, by radiating heat exactly at the bandgap frequency of a photovoltaic cell). However, thermal transport in this regime has never been achieved experimentally due to the difficulty of maintaining large thermal gradients over nanometre-scale distances while avoiding other heat transfer mechanisms, namely conduction. Here, we show near-field radiative heat transfer between parallel SiC nanobeams in the deep subwavelength regime. The distance between the beams is controlled by a high-precision micro-electromechanical system (MEMS). We exploit the mechanical stability of nanobeams under high tensile stress to minimize thermal buckling effects, therefore keeping control of the nanometre-scale separation even at large thermal gradients. We achieve an enhancement of heat transfer of almost two orders of magnitude with respect to the far-field limit (corresponding to a 42 nm separation) and show that we can maintain a temperature gradient of 260 K between the cold and hot surfaces at ∼100 nm distance.

    View details for DOI 10.1038/NNANO.2016.20

    View details for Web of Science ID 000377476800009

    View details for PubMedID 26950243

  • Exceptional Contours and Band Structure Design in Parity-Time Symmetric Photonic Crystals PHYSICAL REVIEW LETTERS Cerjan, A., Raman, A., Fan, S. 2016; 116 (20)

    Abstract

    We investigate the properties of two-dimensional parity-time symmetric periodic systems whose non-Hermitian periodicity is an integer multiple of the underlying Hermitian system's periodicity. This creates a natural set of degeneracies that can undergo thresholdless PT transitions. We derive a k·p perturbation theory suited to the continuous eigenvalues of such systems in terms of the modes of the underlying Hermitian system. In photonic crystals, such thresholdless PT transitions are shown to yield significant control over the band structure of the system, and can result in all-angle supercollimation, a PT-superprism effect, and unidirectional behavior.

    View details for DOI 10.1103/PhysRevLett.116.203902

    View details for Web of Science ID 000376267300007

    View details for PubMedID 27258869

  • Thermal-to-electrical energy conversion by diodes under negative illumination PHYSICAL REVIEW B Santhanam, P., Fan, S. 2016; 93 (16)
  • Broadband Absorption Enhancement in Solar Cells with an Atomically Thin Active Layer ACS PHOTONICS Piper, J. R., Fan, S. 2016; 3 (4): 571-577
  • Angle-selective perfect absorption with two-dimensional materials LIGHT-SCIENCE & APPLICATIONS Zhu, L., Liu, F., Lin, H., Hu, J., Yu, Z., Wang, X., Fan, S. 2016; 5

    Abstract

    Two-dimensional (2D) materials have great potential in photonic and optoelectronic devices. However, the relatively weak light absorption in 2D materials hinders their application in practical devices. Here, we propose a general approach to achieve angle-selective perfect light absorption in 2D materials. As a demonstration of the concept, we experimentally show giant light absorption by placing large-area single-layer graphene on a structure consisting of a chalcogenide layer atop a mirror and achieving a total absorption of 77.6% in the mid-infrared wavelength range (~13 μm), where the graphene contributes a record-high 47.2% absorptivity of mid-infrared light. Construction of such an angle-selective thin optical element is important for solar and thermal energy harvesting, photo-detection and sensing applications. Our study points to a new opportunity to combine 2D materials with photonic structures to enable novel device applications.

    View details for DOI 10.1038/lsa.2016.52

    View details for Web of Science ID 000374463100007

    View details for PubMedCentralID PMC6059899

  • Angle-selective perfect absorption with two-dimensional materials. Light, science & applications Zhu, L., Liu, F., Lin, H., Hu, J., Yu, Z., Wang, X., Fan, S. 2016; 5 (3): e16052

    Abstract

    Two-dimensional (2D) materials have great potential in photonic and optoelectronic devices. However, the relatively weak light absorption in 2D materials hinders their application in practical devices. Here, we propose a general approach to achieve angle-selective perfect light absorption in 2D materials. As a demonstration of the concept, we experimentally show giant light absorption by placing large-area single-layer graphene on a structure consisting of a chalcogenide layer atop a mirror and achieving a total absorption of 77.6% in the mid-infrared wavelength range (~13 μm), where the graphene contributes a record-high 47.2% absorptivity of mid-infrared light. Construction of such an angle-selective thin optical element is important for solar and thermal energy harvesting, photo-detection and sensing applications. Our study points to a new opportunity to combine 2D materials with photonic structures to enable novel device applications.

    View details for DOI 10.1038/lsa.2016.52

    View details for PubMedID 30167153

    View details for PubMedCentralID PMC6059899

  • Controlling the electrostatic Coulomb interaction using metamaterials PHYSICAL REVIEW B Karakasoglu, I., Fan, S. 2016; 93 (7)
  • Photonic gauge potential in a system with a synthetic frequency dimension OPTICS LETTERS Yuan, L., Shi, Y., Fan, S. 2016; 41 (4): 741-744

    Abstract

    We generalize the concept of photonic gauge potential in real space by introducing an additional "synthetic" frequency dimension in addition to the real space dimensions. As an illustration, we consider a one-dimensional array of ring resonators, each supporting a set of resonant modes having a frequency comb with spacing Ω, and undergoing a refractive index modulation at the modulation frequency equal to Ω. We show that the modulation phase provides a gauge potential in the synthetic two-dimensional space with the dimensions being the frequency and the spatial axes. Such a gauge potential can create a topologically protected one-way edge state in the synthetic space that is useful for high-efficiency generation of higher-order side bands.

    View details for DOI 10.1364/OL.41.000741

    View details for Web of Science ID 000369942900022

    View details for PubMedID 26872177

  • Dynamic non-reciprocal meta-surfaces with arbitrary phase reconfigurability based on photonic transition in meta-atoms APPLIED PHYSICS LETTERS Shi, Y., Fan, S. 2016; 108 (2)

    View details for DOI 10.1063/1.4939915

    View details for Web of Science ID 000370258400009

  • Passively Cooling Water below the Ambient Temperature during the Day Via Radiative Sky Cooling Goldstein, E. A., Raman, A. P., Fan, S., ASHRAE AMER SOC HEATING, REFRIGERATING AND AIR-CONDITIONING ENGS. 2016
  • Hyperbolic Weyl Point in Reciprocal Chiral Metamaterial Xiao, M., Lin, Q., Fan, S., IEEE IEEE. 2016: 977
  • Photonic Structure Textile Design for Localized Thermal Management via Radiative Cooling Catrysse, P. B., Song, A. Y., Fan, S., IEEE IEEE. 2016
  • Achieving the gauge potential for the photon in a synthetic space Yuan, L., Shi, Y., Fan, S., IEEE IEEE. 2016
  • Nanophotonic Control of Heat: New Fundamental Effects and Applications Fan, S., IEEE IEEE. 2016
  • Radiative cooling of solar absorbers using a transparent photonic crystal thermal blackbody Zhu, L., Raman, A. R., Fan, S., IEEE IEEE. 2016
  • Current-Voltage Enhancement of a Single Coaxial Nanowire Solar Cell ACS PHOTONICS Sandhu, S., Fan, S. 2015; 2 (12): 1698-1704
  • Achieving nonreciprocal unidirectional single-photon quantum transport using the photonic Aharonov-Bohm effect OPTICS LETTERS Yuan, L., Xu, S., Fan, S. 2015; 40 (22): 5140-5143

    Abstract

    We show that nonreciprocal unidirectional single-photon quantum transport can be achieved with the photonic Aharonov-Bohm effect. The system consists of a 1D waveguide coupling to two three-level atoms of the V-type. The two atoms, in addition, are each driven by an external coherent field. We show that the phase of the external coherent field provides a gauge potential for the photon states. With a proper choice of the phase difference between the two coherent fields, the transport of a single photon can exhibit unity contrast in its transmissions for the two propagation directions.

    View details for DOI 10.1364/OL.40.005140

    View details for Web of Science ID 000366133400004

    View details for PubMedID 26565819

  • Topologically nontrivial Floquet band structure in a system undergoing photonic transitions in the ultrastrong-coupling regime PHYSICAL REVIEW A Yuan, L., Fan, S. 2015; 92 (5)
  • Unified picture of modal loss rates from microwave to optical frequencies in deep-subwavelength metallic structures: A case study with slot waveguides APPLIED PHYSICS LETTERS Shin, W., Fan, S. 2015; 107 (17)

    View details for DOI 10.1063/1.4934707

    View details for Web of Science ID 000364234200002

  • Photon management for enhanced open-circuit voltage in nanostructured solar cells JOURNAL OF PHYSICS D-APPLIED PHYSICS Sandhu, S., Yu, Z., Fan, S. 2015; 48 (41)
  • Analytical treatment of near-field electromagnetic heat transfer at the nanoscale PHYSICAL REVIEW B Iizuka, H., Fan, S. 2015; 92 (14)
  • Radiative cooling of solar absorbers using a visibly transparent photonic crystal thermal blackbody PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Zhu, L., Raman, A. P., Fan, S. 2015; 112 (40): 12282-12287

    Abstract

    A solar absorber, under the sun, is heated up by sunlight. In many applications, including solar cells and outdoor structures, the absorption of sunlight is intrinsic for either operational or aesthetic considerations, but the resulting heating is undesirable. Because a solar absorber by necessity faces the sky, it also naturally has radiative access to the coldness of the universe. Therefore, in these applications it would be very attractive to directly use the sky as a heat sink while preserving solar absorption properties. Here we experimentally demonstrate a visibly transparent thermal blackbody, based on a silica photonic crystal. When placed on a silicon absorber under sunlight, such a blackbody preserves or even slightly enhances sunlight absorption, but reduces the temperature of the underlying silicon absorber by as much as 13 °C due to radiative cooling. Our work shows that the concept of radiative cooling can be used in combination with the utilization of sunlight, enabling new technological capabilities.

    View details for DOI 10.1073/pnas.1509453112

    View details for Web of Science ID 000363125400032

    View details for PubMedID 26392542

    View details for PubMedCentralID PMC4603484

  • Suppressing sub-bandgap phonon-polariton heat transfer in near-field thermophotovoltaic devices for waste heat recovery APPLIED PHYSICS LETTERS Chen, K., Santhanam, P., Fan, S. 2015; 107 (9)

    View details for DOI 10.1063/1.4929949

    View details for Web of Science ID 000360926200006

  • Plasmonic coaxial waveguide-cavity devices OPTICS EXPRESS Mahigir, A., Dastmalchi, P., Shin, W., Fan, S., Veronis, G. 2015; 23 (16): 20549-20562

    Abstract

    We theoretically investigate three-dimensional plasmonic waveguide-cavity structures, built by side-coupling stub resonators that consist of plasmonic coaxial waveguides of finite length, to a plasmonic coaxial waveguide. The resonators are terminated either in a short or an open circuit. We show that the properties of these waveguide-cavity systems can be accurately described using a single-mode scattering matrix theory. We also show that, with proper choice of their design parameters, three-dimensional plasmonic coaxial waveguide-cavity devices and two-dimensional metal-dielectric-metal devices can have nearly identical transmission spectra. Thus, three-dimensional plasmonic coaxial waveguides offer a platform for practical implementation of two-dimensional metal-dielectric-metal device designs.

    View details for DOI 10.1364/OE.23.020549

    View details for Web of Science ID 000361036400031

    View details for PubMedID 26367907

  • Theory of Half-Space Light Absorption Enhancement for Leaky Mode Resonant Nanowires NANO LETTERS Jia, Y., Qiu, M., Wu, H., Cui, Y., Fan, S., Ruan, Z. 2015; 15 (8): 5513-5518

    Abstract

    Semiconductor nanowires supporting leaky mode resonances have been used to increase light absorption in optoelectronic applications from solar cell to photodetector and sensor. The light conventionally illuminates these devices with a wide range of different incident angles from half space. Currently, most of the investigated nanowires have centrosymmetric geometry cross section, such as circle, hexagon, and rectangle. Here we show that the absorption capability of these symmetrical nanowires has an upper limit under the half-space illumination. Based on the temporal coupled-mode equation, we develop a reciprocity theory for leaky mode resonances in order to connect the angle-dependent absorption cross section and the radiation pattern. We show that in order to exceed such a half-space limit the radiation pattern should be noncentrosymmetric and dominate in the direction reciprocal to the illumination. As an example, we design a metal trough structure to achieve the desired radiation pattern for an embedded nanowire. In comparison to a single nanowire case the trough structure indeed overcomes the half-space limit and leads to 39% and 64% absorption enhancement in TM and TE polarizations, respectively. Also the trough structure enables the enhancement over a broad wavelength range.

    View details for DOI 10.1021/acs.nanolett.5b02044

    View details for PubMedID 26171950

  • Analog of superradiant emission in thermal emitters PHYSICAL REVIEW B Zhou, M., Yi, S., Luk, T., Gan, Q., Fan, S., Yu, Z. 2015; 92 (2)
  • Resonator-free realization of effective magnetic field for photons NEW JOURNAL OF PHYSICS Lin, Q., Fan, S. 2015; 17
  • Optical-Electronic Analysis of the Intrinsic Behaviors of Nanostructured Ultrathin Crystalline Silicon Solar Cells ACS PHOTONICS Karakasoglu, I., Wang, K. X., Fan, S. 2015; 2 (7): 883-889
  • Three-Dimensional Dynamic Localization of Light from a Time-Dependent Effective Gauge Field for Photons PHYSICAL REVIEW LETTERS Yuan, L., Fan, S. 2015; 114 (24)

    Abstract

    We introduce a method to achieve the three-dimensional dynamic localization of light. We consider a dynamically modulated resonator lattice that has been previously shown to exhibit an effective gauge potential for photons. When such an effective gauge potential varies sinusoidally in time, dynamic localization of light can be achieved. Moreover, while previous works on such an effective gauge potential for photons were carried out in the regime where the rotating wave approximation is valid, the effect of dynamic localization persists even when the counterrotating term is taken into count.

    View details for DOI 10.1103/PhysRevLett.114.243901

    View details for Web of Science ID 000356221000004

    View details for PubMedID 26196977

  • Limitations of nonlinear optical isolators due to dynamic reciprocity NATURE PHOTONICS Shi, Y., Yu, Z., Fan, S. 2015; 9 (6): 388-392
  • Input-output formalism for few-photon transport: A systematic treatment beyond two photons PHYSICAL REVIEW A Xu, S., Fan, S. 2015; 91 (4)
  • Heat-flux control and solid-state cooling by regulating chemical potential of photons in near-field electromagnetic heat transfer PHYSICAL REVIEW B Chen, K., Santhanam, P., Sandhu, S., Zhu, L., Fan, S. 2015; 91 (13)
  • Optical separation of heterogeneous size distributions of microparticles on silicon nitride strip waveguides OPTICS EXPRESS Khan, S. A., Shi, Y., Chang, C., Jan, C., Fan, S., Ellerbee, A. K., Solgaard, O. 2015; 23 (7): 8855-8866

    Abstract

    We demonstrate two complementary optical separation techniques of dielectric particles on the surface of silicon nitride waveguides. Glass particles ranging from 2 μm to 10 μm in diameter are separated at guided powers below 40 mW. The effects of optical, viscous, and frictional forces on the particles are modeled and experimentally shown to enable separation. Particle interactions are investigated and shown to decrease measured particle velocity without interfering with the overall particle separation distribution. The demonstrated separation techniques have the potential to be integrated with microfluidic structures for cell sorting.

    View details for DOI 10.1364/OE.23.008855

    View details for Web of Science ID 000352290000088

    View details for PubMedID 25968723

  • Planar immersion lens with metasurfaces PHYSICAL REVIEW B Ho, J. S., Qiu, B., Tanabe, Y., Yeh, A. J., Fan, S., Poon, A. S. 2015; 91 (12)
  • Near-Field Radiative Heat Transfer between Integrated Nanostructures using Silicon Carbide St-Gelais, R., Zhu, L., Guha, B., Fan, S., Lipson, M., IEEE IEEE. 2015
  • Radiative cooling for solar cells Conference on Physics, Simulation, and Photonic Engineering of Photovoltaic Devices IV Zhu, L., Raman, A., Wang, K. X., Abou Anoma, M., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2015

    View details for DOI 10.1117/12.2080148

    View details for Web of Science ID 000353897400026

  • Sufficient Condition for Perfect Antireflection by Optical Resonance at Dielectric Interface Conference on Physics, Simulation, and Photonic Engineering of Photovoltaic Devices IV Wang, K. X., Yu, Z., Sandhu, S., Liu, V., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2015

    View details for DOI 10.1117/12.2076242

    View details for Web of Science ID 000353897400002

  • Light Guiding by Gauge Field for Photons Lin, Q., Fan, S., IEEE IEEE. 2015
  • Routing of deep-subwavelength optical beams without reflection and diffraction using infinitely anisotropic metamaterials Catrysse, P. B., Fan, S., Betz, M., Elezzabi, A. Y., Tsen, K. T. SPIE-INT SOC OPTICAL ENGINEERING. 2015

    View details for DOI 10.1117/12.2081040

    View details for Web of Science ID 000354276800015

  • Condition for Perfect Resonant Antireflection in Solar Cells Wang, K., Yu, Z., Sandhu, S., Liu, V., Fan, S., IEEE IEEE. 2015
  • Theory and Practice of Resonant Antireflection Wang, K., Fan, S., IEEE IEEE. 2015
  • Recent advances on non-reciprocal light manipulation from dynamic modulation Fan, S., Shi, Y., Yu, Z., Lin, Q., Yuan, L., IEEE IEEE. 2015: 400–402
  • Using time-dependent effective gauge field for photons to achieve dynamic localization of light Yuan, L., Fan, S., Subramania, G. S., Foteinopoulou, S. SPIE-INT SOC OPTICAL ENGINEERING. 2015

    View details for DOI 10.1117/12.2189528

    View details for Web of Science ID 000365749100034

  • Near complete violation of detailed balance in thermal radiation Zhu, L., Fan, S., IEEE IEEE. 2015
  • Condition for perfect antireflection by optical resonance at material interface OPTICA Wang, K. X., Yu, Z., Sandhu, S., Liu, V., Fan, S. 2014; 1 (6): 388-395
  • Near-complete violation of detailed balance in thermal radiation PHYSICAL REVIEW B Zhu, L., Fan, S. 2014; 90 (22)
  • Demonstration of Strong Near-Field Radiative Heat Transfer between Integrated Nanostructures NANO LETTERS St-Gelais, R., Guha, B., Zhu, L., Fan, S., Lipson, M. 2014; 14 (12): 6971-6975

    Abstract

    Near-field heat transfer recently attracted growing interest but was demonstrated experimentally only in macroscopic systems. However, several projected applications would be relevant mostly in integrated nanostructures. Here we demonstrate a platform for near-field heat transfer on-chip and show that it can be the dominant thermal transport mechanism between integrated nanostructures, overcoming background substrate conduction and the far-field limit (by factors 8 and 7, respectively). Our approach could enable the development of active thermal control devices such as thermal rectifiers and transistors.

    View details for DOI 10.1021/nl503236k

    View details for Web of Science ID 000346322800034

    View details for PubMedID 25420115

  • Passive radiative cooling below ambient air temperature under direct sunlight. Nature Raman, A. P., Anoma, M. A., Zhu, L., Rephaeli, E., Fan, S. 2014; 515 (7528): 540-544

    Abstract

    Cooling is a significant end-use of energy globally and a major driver of peak electricity demand. Air conditioning, for example, accounts for nearly fifteen per cent of the primary energy used by buildings in the United States. A passive cooling strategy that cools without any electricity input could therefore have a significant impact on global energy consumption. To achieve cooling one needs to be able to reach and maintain a temperature below that of the ambient air. At night, passive cooling below ambient air temperature has been demonstrated using a technique known as radiative cooling, in which a device exposed to the sky is used to radiate heat to outer space through a transparency window in the atmosphere between 8 and 13 micrometres. Peak cooling demand, however, occurs during the daytime. Daytime radiative cooling to a temperature below ambient of a surface under direct sunlight has not been achieved because sky access during the day results in heating of the radiative cooler by the Sun. Here, we experimentally demonstrate radiative cooling to nearly 5 degrees Celsius below the ambient air temperature under direct sunlight. Using a thermal photonic approach, we introduce an integrated photonic solar reflector and thermal emitter consisting of seven layers of HfO2 and SiO2 that reflects 97 per cent of incident sunlight while emitting strongly and selectively in the atmospheric transparency window. When exposed to direct sunlight exceeding 850 watts per square metre on a rooftop, the photonic radiative cooler cools to 4.9 degrees Celsius below ambient air temperature, and has a cooling power of 40.1 watts per square metre at ambient air temperature. These results demonstrate that a tailored, photonic approach can fundamentally enable new technological possibilities for energy efficiency. Further, the cold darkness of the Universe can be used as a renewable thermodynamic resource, even during the hottest hours of the day.

    View details for DOI 10.1038/nature13883

    View details for PubMedID 25428501

  • Accelerating simulation of ensembles of locally differing optical structures via a Schur complement domain decomposition OPTICS LETTERS Verweij, S., Liu, V., Fan, S. 2014; 39 (22): 6458-6461

    Abstract

    We present a Schur complement domain decomposition method that can significantly accelerate simulation of ensembles of locally differing optical structures. We apply the method to design a multi-spatial-mode photonic crystal waveguide splitter that exhibits high transmission and preservation of modal content, showing design acceleration by more than a factor of 20.

    View details for DOI 10.1364/OL.39.006458

    View details for Web of Science ID 000344986000026

  • Approaching total absorption at near infrared in a large area monolayer graphene by critical coupling APPLIED PHYSICS LETTERS Liu, Y., Chadha, A., Zhao, D., Piper, J. R., Jia, Y., Shuai, Y., Menon, L., Yang, H., Ma, Z., Fan, S., Xia, F., Zhou, W. 2014; 105 (18)

    View details for DOI 10.1063/1.4901181

    View details for Web of Science ID 000345000000005

  • Consideration of enhancement of thermal rectification using metamaterial models JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Iizuka, H., Fan, S. 2014; 148: 156-164
  • Complete power concentration into a single waveguide in large-scale waveguide array lenses SCIENTIFIC REPORTS Catrysse, P. B., Liu, V., Fan, S. 2014; 4

    Abstract

    Waveguide array lenses are waveguide arrays that focus light incident on all waveguides at the input side into a small number of waveguides at the output side. Ideal waveguide array lenses provide complete (100%) power concentration of incident light into a single waveguide. While of great interest for several applications, ideal waveguide array lenses have not been demonstrated for practical arrays with large numbers of waveguides. The only waveguide arrays that have sufficient degrees of freedom to allow for the design of an ideal waveguide array lens are those where both the propagation constants of the individual waveguides and the coupling constants between the waveguides vary as a function of space. Here, we use state-of-the-art numerical methods to demonstrate complete power transfer into a single waveguide for waveguide array lenses with large numbers of waveguides. We verify this capability for more than a thousand waveguides using a spatial coupled mode theory. We hereby extend the state-of-art by more than two orders of magnitude. We also demonstrate for the first time a physical design for an ideal waveguide array lens. The design is based on an aperiodic metallic waveguide array and focuses ~100% of the incident light into a deep-subwavelength focal spot.

    View details for DOI 10.1038/srep06635

    View details for Web of Science ID 000343089300005

    View details for PubMedID 25319203

    View details for PubMedCentralID PMC4198864

  • Graphene surface plasmons at the near-infrared optical regime SCIENTIFIC REPORTS Zhang, Q., Li, X., Hossain, M. M., Xue, Y., Zhang, J., Song, J., Liu, J., Turner, M. D., Fan, S., Bao, Q., Gu, M. 2014; 4

    Abstract

    Graphene has been identified as an emerging horizon for a nanoscale photonic platform because the Fermi level of intrinsic graphene can be engineered to support surface plasmons (SPs). The current solid back electrical gating and chemical doping methods cannot facilitate the demonstration of graphene SPs at the near-infrared (NIR) window because of the limited shift of the Fermi level. Here, we present the evidence for the existence of graphene SPs on a tapered graphene-silicon waveguide tip at a NIR wavelength, employing a surface carrier transfer method with molybdenum trioxides. The coupling between the graphene surface plasmons and the guiding mode in silicon waveguides allows for the observation of the concentrated field of the SPs in the tip by near-field scanning optical microscopy. Thus the hot spot from the concentrated SPs in the graphene layer can be used as a key experimental signature of graphene SPs. The NIR graphene SPs opens a new perspective for optical communications, optical sensing and imaging, and optical data storage with extreme spatial confinement, broad bandwidth and high tunability.

    View details for DOI 10.1038/srep06559

    View details for Web of Science ID 000343060300006

    View details for PubMedID 25297570

    View details for PubMedCentralID PMC4190570

  • Two-dimensional Green's tensor for gyrotropic clusters composed of circular cylinders JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION Asatryan, A. A., Botten, L. C., Fang, K., Fan, S., McPhedran, R. C. 2014; 31 (10): 2294-2303

    Abstract

    The construction of Green's tensor for two-dimensional gyrotropic photonic clusters composed of cylinders with circular cross sections using the semi-analytic multipole method is presented. The high efficiency and accuracy of the method is demonstrated. The developed method is applied to gyrotropic clusters that support topological chiral Hall edge states. The remarkable tolerance of chiral Hall edge modes toward substantial cluster separation is revealed. The transformation of chiral Hall edge states as the cluster separation increases is also presented. The excitation of chiral Hall edge modes for different source orientations is considered. Both gyroelectric and gyromagnetic (ferrite) clusters are treated.

    View details for DOI 10.1364/JOSAA.31.002294

    View details for Web of Science ID 000344781600026

    View details for PubMedID 25401258

  • Non-reciprocal phase shift induced by an effective magnetic flux for light NATURE PHOTONICS Tzuang, L. D., Fang, K., Nussenzveig, P., Fan, S., Lipson, M. 2014; 8 (9): 701-705
  • Light Guiding by Effective Gauge Field for Photons PHYSICAL REVIEW X Lin, Q., Fan, S. 2014; 4 (3)
  • Directional perfect absorption using deep subwavelength low-permittivity films PHYSICAL REVIEW B Luk, T. S., Campione, S., Kim, I., Feng, S., Jun, Y. C., Liu, S., Wright, J. B., Brener, I., Catrysse, P. B., Fan, S., Sinclair, M. B. 2014; 90 (8)
  • Light trapping in photonic crystals ENERGY & ENVIRONMENTAL SCIENCE Wang, K. X., Yu, Z., Liu, V., Raman, A., Cui, Y., Fan, S. 2014; 7 (8): 2725-2738

    View details for DOI 10.1039/c4ee00839a

    View details for Web of Science ID 000339861800029

  • Radiative cooling of solar cells OPTICA Zhu, L., Raman, A., Wang, K. X., Abou Anoma, M., Fan, S. 2014; 1 (1): 32-38
  • Spectral light separator based on deep-subwavelength resonant apertures in a metallic film APPLIED PHYSICS LETTERS Bueyuekalp, Y., Catrysse, P. B., Shin, W., Fan, S. 2014; 105 (1)

    View details for DOI 10.1063/1.4887059

    View details for Web of Science ID 000339664900014

  • Dislocated Double-Layer Metal Gratings: An Efficient Unidirectional Coupler NANO LETTERS Liu, T., Shen, Y., Shin, W., Zhu, Q., Fan, S., Jin, C. 2014; 14 (7): 3848-3854

    Abstract

    We propose theoretically and demonstrate experimentally a dislocated double-layer metal grating structure, which operates as a unidirectional coupler capable of launching surface plasmon polaritons in a desired direction under normal illumination. The structure consists of a slanted dielectric grating sandwiched between two gold gratings. The upper gold grating has a nonzero lateral relative displacement with respect to the lower one. Numerical simulations show that a grating structure with 7 periods can convert 49% of normally incident light into surface plasmons with a contrast ratio of 78 between the powers of the surface plasmons launched in two opposite directions. We explain the unidirectional coupling phenomenon by the dislocation-induced interference of the diffracted waves from the upper and lower gold gratings. Furthermore, we developed a simple and cost-effective technique to fabricate the structure via tilted two-beam interference lithography and subsequent shadow deposition of gold. The experimental results demonstrate a coupling efficiency of 36% and a contrast ratio of 43. The relatively simple periodic nature of our structure lends itself to large-scale low-cost fabrication and simple theoretical analysis. Also, unlike the previous unidirectional couplers based on aperiodic structures, the design parameters of our unidirectional coupler can be determined analytically. Therefore, this structure can be an important component for surface-plasmon-based nanophotonic circuits by providing an efficient interface between free-space and surface plasmon waves.

    View details for DOI 10.1021/nl501007d

    View details for Web of Science ID 000338979700023

    View details for PubMedID 24926990

  • Total absorption by degenerate critical coupling APPLIED PHYSICS LETTERS Piper, J. R., Liu, V., Fan, S. 2014; 104 (25)

    View details for DOI 10.1063/1.4885517

    View details for Web of Science ID 000338515900010

  • Spatial control of surface plasmon polariton excitation at planar metal surface OPTICS LETTERS Ruan, Z., Wu, H., Qiu, M., Fan, S. 2014; 39 (12): 3587-3590

    Abstract

    We illustrate that the surface plasmon polariton (SPP) excitation through the prism coupling method is fundamentally limited by destructive interference of spatial light components. We propose that the destructive interference can be canceled out by tailoring the relative phase for the different wave-vector components. As a numerical demonstration, we show that through the phase modulation the excited SPP field is concentrated to a hot energy spot, and the SPP field intensity is dramatically enhanced about three-fold in comparison with a conventional Gaussian beam illumination. The proposed phase-shaped beam approach provides a new degree of freedom to fundamentally control the SPP excitation and benefits the development of surface-enhanced applications.

    View details for DOI 10.1364/OL.39.003587

    View details for Web of Science ID 000338870500058

    View details for PubMedID 24978543

  • Sensitivity analysis and optimization of sub-wavelength optical gratings using adjoints OPTICS EXPRESS Niederberger, A. R., Fattal, D. A., Gauger, N. R., Fan, S., Beausoleil, R. G. 2014; 22 (11): 12971-12981

    Abstract

    Numerical optimization of photonic devices is often limited by a large design space the finite-differences gradient method requires as many electric field computations as there are design parameters. Adjoint-based optimization can deliver the same gradients with only two electric field computations. Here, we derive the relevant adjoint formalism and illustrate its application for a waveguide slab, and for the design of optical sub-wavelength gratings.

    View details for DOI 10.1364/OE.22.012971

    View details for Web of Science ID 000337501600027

    View details for PubMedID 24921494

  • Optical impedance transformer for transparent conducting electrodes. Nano letters Wang, K. X., Piper, J. R., Fan, S. 2014; 14 (5): 2755-2758

    Abstract

    A fundamental limitation of transparent conducting electrode design is thought to be the trade-off between photonic and electronic performances. The photonic transmission property of a transparent conducting electrode, however, is not intrinsic but depends critically on the electromagnetic environment where the electrode is located. We develop the concept of optical impedance transformation, and use this concept to design nanophotonic structures that provide broadband and omnidirectional reduction of optical loss in an ultrathin transparent conducting electrode, without compromising its electrical performance.

    View details for DOI 10.1021/nl500741f

    View details for PubMedID 24773302

  • Optical Fano resonance of an individual semiconductor nanostructure NATURE MATERIALS Fan, P., Yu, Z., Fan, S., Brongersma, M. L. 2014; 13 (5): 471-475

    Abstract

    Fano resonances with a characteristic asymmetric line shape can be observed in light scattering, transmission and reflection spectra of resonant optical systems. They result from interference between direct and indirect, resonance-assisted pathways. In the nanophotonics field, Fano effects have been observed in a wide variety of systems, including metallic nanoparticle assemblies, metamaterials and photonic crystals. Their unique properties find extensive use in applications, including optical filtering, polarization selectors, sensing, lasers, modulators and nonlinear optics. We report on the observation of a Fano resonance in a single semiconductor nanostructure, opening up opportunities for their use in active photonic devices. We also show that Fano-resonant semiconductor nanostructures afford the intriguing opportunity to simultaneously measure the far-field scattering response and the near-field energy storage by extracting photogenerated charge. Together they can provide a complete experimental characterization of this type of resonance.

    View details for DOI 10.1038/NMAT3927

    View details for Web of Science ID 000334845600017

    View details for PubMedID 24747781

  • Parity-time-symmetric whispering-gallery microcavities NATURE PHYSICS Peng, B., Oezdemir, S. K., Lei, F., Monifi, F., Gianfreda, M., Long, G. L., Fan, S., Nori, F., Bender, C. M., Yang, L. 2014; 10 (5): 394-398

    View details for DOI 10.1038/NPHYS2927

    View details for Web of Science ID 000335371200019

  • Light management for photovoltaics using high-index nanostructures NATURE MATERIALS Brongersma, M. L., Cui, Y., Fan, S. 2014; 13 (5): 451-460

    Abstract

    High-performance photovoltaic cells use semiconductors to convert sunlight into clean electrical power, and transparent dielectrics or conductive oxides as antireflection coatings. A common feature of these materials is their high refractive index. Whereas high-index materials in a planar form tend to produce a strong, undesired reflection of sunlight, high-index nanostructures afford new ways to manipulate light at a subwavelength scale. For example, nanoscale wires, particles and voids support strong optical resonances that can enhance and effectively control light absorption and scattering processes. As such, they provide ideal building blocks for novel, broadband antireflection coatings, light-trapping layers and super-absorbing films. This Review discusses some of the recent developments in the design and implementation of such photonic elements in thin-film photovoltaic cells.

    View details for DOI 10.1038/NMAT3921

    View details for Web of Science ID 000334845600014

    View details for PubMedID 24751773

  • Total Absorption in a Graphene Mono layer in the Optical Regime by Critical Coupling with a Photonic Crystal Guided Resonance ACS PHOTONICS Piper, J. R., Fan, S. 2014; 1 (4): 347-353

    View details for DOI 10.1021/ph400090p

    View details for Web of Science ID 000335805200008

  • Nanoscale thermal transport. II. 2003-2012 APPLIED PHYSICS REVIEWS Cahill, D. G., Braun, P. V., Chen, G., Clarke, D. R., Fan, S., Goodson, K. E., Keblinski, P., King, W. P., Mahan, G. D., Majumdar, A., Maris, H. J., Phillpot, S. R., Pop, E., Shi, L. 2014; 1 (1)

    View details for DOI 10.1063/1.4832615

    View details for Web of Science ID 000334098500010

  • Energy efficient nanophotonics: Engineered light-matter interaction in sub-wavelength structures OPTICS COMMUNICATIONS Husko, C., Yu, Z., Fan, S. 2014; 314: 1-2
  • Nearly Total Solar Absorption in Ultrathin Nanostructured Iron Oxide for Efficient Photoelectrochemical Water Splitting ACS PHOTONICS Wang, K. X., Wu, Z., Liu, V., Brongersma, M. L., Jaramillo, T. F., Fan, S. 2014; 1 (3): 235-240

    View details for DOI 10.1021/ph4001026

    View details for Web of Science ID 000335802900013

  • Detailed balance analysis and enhancement of open-circuit voltage in single-nanowire solar cells. Nano letters Sandhu, S., Yu, Z., Fan, S. 2014; 14 (2): 1011-1015

    Abstract

    We present a detailed balance analysis of current density-voltage modeling of a single-nanowire solar cell. Our analysis takes into account intrinsic material nonidealities in order to determine the theoretical efficiency limit of the single-nanowire solar cell. The analysis only requires the nanowire's absorption cross-section over all angles, which can be readily calculated analytically. We show that the behavior of both the current and voltage is due to coherent effects that arise from resonances of the nanowire. In addition, we elucidate the physics of open-circuit voltage enhancement over bulk cells in nanowires, by showing that the enhancement is related to the removal of resonances in the immediate spectral vicinity above the bandgap.

    View details for DOI 10.1021/nl404501w

    View details for PubMedID 24479660

  • Fluctuational electrodynamics calculations of near-field heat transfer in non-planar geometries: A brief overview JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER Otey, C. R., Zhu, L., Sandhu, S., Fan, S. 2014; 132: 3-11
  • Large-scale ideal waveguide lenses with complete power concentration in a single waveguide Catrysse, P. B., Liu, V., Fan, S., IEEE IEEE. 2014
  • Optical Impedance Transformer for Transparent Conducting Electrodes Carbon Nanotubes, Graphene,and Associated Devices VII Wang, K. X., Piper, J. R., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2014

    View details for DOI 10.1117/12.2061159

    View details for Web of Science ID 000343860300002

  • Color-preserving daytime radiative cooling Zhu, L., Raman, A., Fan, S., IEEE IEEE. 2014
  • Demonstration of Strong Near-Field Radiative Heat Transfer between Nanostructures St-Gelais, R., Guha, B., Zhu, L., Fan, S., Lipson, M., IEEE IEEE. 2014
  • Parity-time (PT)-symmetric optical microcavities Peng, B., Oezdemir, S., Fan, S., Nori, F., Gianfreda, M., Bender, C. M., Yang, L., IEEE IEEE. 2014
  • Observation of an effective magnetic field for light Tzuang, L. D., Fang, K., Nussenzveig, P., Fan, S., Lipson, M., IEEE IEEE. 2014
  • Nanophotonic Light Trapping Theory for Photovoltaics NANOFABRICATION AND ITS APPLICATION IN RENEWABLE ENERGY Yu, Z., Raman, A., Fan, S., Zhang, G., Manjooran, N. 2014: 31-61
  • Optical Impedance Transformer for Transparent Conducting Electrodes Wang, K., Fan, S., IEEE IEEE. 2014: 542–43
  • Photovoltaics: an alternative 'Sun' for solar cells. Nature nanotechnology Fan, S. n. 2014; 9 (2): 92–93

    View details for PubMedID 24496275

  • Towards ultra-thin plasmonic silicon wafer solar cells with minimized efficiency loss. Scientific reports Zhang, Y. n., Stokes, N. n., Jia, B. n., Fan, S. n., Gu, M. n. 2014; 4: 4939

    Abstract

    The cost-effectiveness of market-dominating silicon wafer solar cells plays a key role in determining the competiveness of solar energy with other exhaustible energy sources. Reducing the silicon wafer thickness at a minimized efficiency loss represents a mainstream trend in increasing the cost-effectiveness of wafer-based solar cells. In this paper we demonstrate that, using the advanced light trapping strategy with a properly designed nanoparticle architecture, the wafer thickness can be dramatically reduced to only around 1/10 of the current thickness (180 μm) without any solar cell efficiency loss at 18.2%. Nanoparticle integrated ultra-thin solar cells with only 3% of the current wafer thickness can potentially achieve 15.3% efficiency combining the absorption enhancement with the benefit of thinner wafer induced open circuit voltage increase. This represents a 97% material saving with only 15% relative efficiency loss. These results demonstrate the feasibility and prospect of achieving high-efficiency ultra-thin silicon wafer cells with plasmonic light trapping.

    View details for PubMedID 24820403

    View details for PubMedCentralID PMC4018607

  • Photonic Aharonov-Bohm effect in photon-phonon interactions NATURE COMMUNICATIONS Li, E., Eggleton, B. J., Fang, K., Fan, S. 2014; 5

    Abstract

    The Aharonov-Bohm effect is one of the most intriguing phenomena in both classical and quantum physics, and associates with a number of important and fundamental issues in quantum mechanics. The Aharonov-Bohm effects of charged particles have been experimentally demonstrated and found applications in various fields. Recently, attention has also focused on the Aharonov-Bohm effect for neutral particles, such as photons. Here we propose to utilize the photon-phonon interactions to demonstrate that photonic Aharonov-Bohm effects do exist for photons. By introducing nonreciprocal phases for photons, we observe experimentally a gauge potential for photons in the visible range based on the photon-phonon interactions in acousto-optic crystals, and demonstrate the photonic Aharonov-Bohm effect. The results presented here point to new possibilities to control and manipulate photons by designing an effective gauge potential.

    View details for DOI 10.1038/ncomms4225

    View details for Web of Science ID 000331141700001

    View details for PubMedID 24476790

    View details for PubMedCentralID PMC3916835

  • Progress in 2D photonic crystal Fano resonance photonics PROGRESS IN QUANTUM ELECTRONICS Zhou, W., Zhao, D., Shuai, Y., Yang, H., Chuwongin, S., Chadha, A., Seo, J., Wang, K. X., Liu, V., Ma, Z., Fan, S. 2014; 38 (1): 1-74
  • Light Trapping in Photonic Crystals Conference on Thin Films for Solar and Energy Technology VI Wang, K. X., Yu, Z., Liu, V., Raman, A., Cui, Y., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2014

    View details for DOI 10.1117/12.2061160

    View details for Web of Science ID 000349362600014

  • Ultrahigh contrast and large-bandwidth thermal rectification in near-field electromagnetic thermal transfer between nanoparticles Conference on Nanophotonic Materials XI Zhu, L., Otey, C. R., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2014

    View details for DOI 10.1117/12.2061262

    View details for Web of Science ID 000344107800012

  • Efficiency above the Shockley-Queisser Limit by Using Nanophotonic Effects To Create Multiple Effective Bandgaps With a Single Semiconductor NANO LETTERS Yu, Z., Sandhu, S., Fan, S. 2014; 14 (1): 66-70

    Abstract

    We present a pure photonic approach to overcome the Shockley-Queisser limit. A single material can show different effective bandgap, set by its absorption spectrum, which depends on its photonic structure. In a tandem cell configuration constructed from a single material, one can achieve two different effective bandgaps, thereby exceeding the Shockley-Queisser limit.

    View details for DOI 10.1021/nl403653j

    View details for Web of Science ID 000329586700011

    View details for PubMedID 24279726

  • Two-dimensional chalcogenide nanoplates as tunable metamaterials via chemical intercalation. Nano letters Cha, J. J., Koski, K. J., Huang, K. C., Wang, K. X., Luo, W., Kong, D., Yu, Z., Fan, S., Brongersma, M. L., Cui, Y. 2013; 13 (12): 5913-5918

    Abstract

    New plasmonic materials with tunable properties are in great need for nanophotonics and metamaterials applications. Here we present two-dimensional layered, metal chalcogenides as tunable metamaterials that feature both dielectric photonic and plasmonic modes across a wide spectral range from the infrared to ultraviolet. The anisotropic layered structure allows intercalation of organic molecules and metal atoms at the van der Waals gap of the host chalcogenide, presenting a chemical route to create heterostructures with molecular and atomic precision for photonic and plasmonic applications. This marks a departure from a lithographic method to create metamaterials. Monochromated electron energy-loss spectroscopy in a scanning transmission electron microscope was used to first establish the presence of the dielectric photonic and plasmonic modes in M2E3 (M = Bi, Sb; E = Se, Te) nanoplates and to observe marked changes in these modes after chemical intercalation. We show that these modal properties can also be tuned effectively by more conventional methods such as thickness control and alloy composition of the nanoplates.

    View details for DOI 10.1021/nl402937g

    View details for PubMedID 24266743

  • Coupled double-layer Fano resonance photonic crystal filters with lattice-displacement APPLIED PHYSICS LETTERS Shuai, Y., Zhao, D., Chadha, A. S., Seo, J., Yang, H., Fan, S., Ma, Z., Zhou, W. 2013; 103 (24)

    View details for DOI 10.1063/1.4846475

    View details for Web of Science ID 000328706500006

  • Deep subwavelength plasmonic waveguide switch in double graphene layer structure APPLIED PHYSICS LETTERS Iizuka, H., Fan, S. 2013; 103 (23)

    View details for DOI 10.1063/1.4839420

    View details for Web of Science ID 000328634900075

  • Metamaterial band theory: fundamentals & applications SCIENCE CHINA-INFORMATION SCIENCES Raman, A. P., Shin, W., Fan, S. 2013; 56 (12)
  • Two-Dimensional Chalcogenide Nanoplates as Tunable Metamaterials via Chemical Intercalation NANO LETTERS Cha, J. J., Koski, K. J., Huang, K. C., Wan, K. X., Luo, W., Kong, D., Yu, Z., Fan, S., Brongersma, M. L., Cui, Y. 2013; 13 (12): 5913-5918

    Abstract

    New plasmonic materials with tunable properties are in great need for nanophotonics and metamaterials applications. Here we present two-dimensional layered, metal chalcogenides as tunable metamaterials that feature both dielectric photonic and plasmonic modes across a wide spectral range from the infrared to ultraviolet. The anisotropic layered structure allows intercalation of organic molecules and metal atoms at the van der Waals gap of the host chalcogenide, presenting a chemical route to create heterostructures with molecular and atomic precision for photonic and plasmonic applications. This marks a departure from a lithographic method to create metamaterials. Monochromated electron energy-loss spectroscopy in a scanning transmission electron microscope was used to first establish the presence of the dielectric photonic and plasmonic modes in M2E3 (M = Bi, Sb; E = Se, Te) nanoplates and to observe marked changes in these modes after chemical intercalation. We show that these modal properties can also be tuned effectively by more conventional methods such as thickness control and alloy composition of the nanoplates.

    View details for DOI 10.1021/nl402937g

    View details for Web of Science ID 000328439200024

  • Analytic properties of two-photon scattering matrix in integrated quantum systems determined by the cluster decomposition principle. Physical review letters Xu, S., Rephaeli, E., Fan, S. 2013; 111 (22): 223602-?

    Abstract

    We consider a general class of integrated quantum systems where photon-photon interaction occurs in a quantum device that is localized in space. Using techniques that are closely related to cluster decomposition principles in quantum field theory, we provide a general constraint on the analytic properties of a two-photon S matrix in this class of systems. We also show that the photon-photon interaction in these systems inevitably leads to frequency mixing and entanglement and that frequencies of the single photons cannot be preserved in these systems.

    View details for PubMedID 24329447

  • Analytic Properties of Two-Photon Scattering Matrix in Integrated Quantum Systems Determined by the Cluster Decomposition Principle PHYSICAL REVIEW LETTERS Xu, S., Rephaeli, E., Fan, S. 2013; 111 (22)

    Abstract

    We consider a general class of integrated quantum systems where photon-photon interaction occurs in a quantum device that is localized in space. Using techniques that are closely related to cluster decomposition principles in quantum field theory, we provide a general constraint on the analytic properties of a two-photon S matrix in this class of systems. We also show that the photon-photon interaction in these systems inevitably leads to frequency mixing and entanglement and that frequencies of the single photons cannot be preserved in these systems.

    View details for DOI 10.1103/PhysRevLett.111.223602

    View details for Web of Science ID 000327941100011

    View details for PubMedID 24329447

  • Color-preserving daytime radiative cooling APPLIED PHYSICS LETTERS Zhu, L., Raman, A., Fan, S. 2013; 103 (22)

    View details for DOI 10.1063/1.4835995

    View details for Web of Science ID 000327696300079

  • Controlling the Flow of Light Using the Inhomogeneous Effective Gauge Field that Emerges from Dynamic Modulation PHYSICAL REVIEW LETTERS Fang, K., Fan, S. 2013; 111 (20)

    Abstract

    We show that the effective gauge field for photons provides a versatile platform for controlling the flow of light. As an example we consider a photonic resonator lattice where the coupling strength between nearest neighbor resonators are harmonically modulated. By choosing different spatial distributions of the modulation phases, and hence imposing different inhomogeneous effective magnetic field configurations, we numerically demonstrate a wide variety of propagation effects including negative refraction, one-way mirror, and on- and off-axis focusing. Since the effective gauge field is imposed dynamically after a structure is constructed, our work points to the importance of the temporal degree of freedom for controlling the spatial flow of light.

    View details for DOI 10.1103/PhysRevLett.111.203901

    View details for Web of Science ID 000327243300002

    View details for PubMedID 24289686

  • Ultrahigh-contrast and large-bandwidth thermal rectification in near-field electromagnetic thermal transfer between nanoparticles PHYSICAL REVIEW B Zhu, L., Otey, C. R., Fan, S. 2013; 88 (18)
  • Effective magnetic field for photons based on the magneto-optical effect PHYSICAL REVIEW A Fang, K., Fan, S. 2013; 88 (4)
  • A lateral optical equilibrium in waveguide-resonator optical force OPTICS EXPRESS Intaraprasonk, V., Fan, S. 2013; 21 (21): 25257-25270

    Abstract

    We consider the lateral optical force between a resonator and a waveguide, and study the possibility of an equilibrium that occurs solely from the optical force in such system. We prove analytically that a single-resonance system cannot give such an equilibrium in the resonator-waveguide force. We then show that two-resonance systems can provide such an equilibrium. We provide an intuitive way to predict the existence of an equilibrium, and give numerical examples.

    View details for DOI 10.1364/OE.21.025257

    View details for Web of Science ID 000326085600080

    View details for PubMedID 24150366

  • Double-layer Fano resonance photonic crystal filters OPTICS EXPRESS Shuai, Y., Zhao, D., Tian, Z., Seo, J., Plant, D. V., Ma, Z., Fan, S., Zhou, W. 2013; 21 (21): 24582-24589

    Abstract

    We report ultra-compact surface-normal high-Q optical filters based on single- and double-layer stacked Fano resonance photonic crystal slabs on both Si and quartz substrates. A single layer photonic crystal filter was designed and a Q factor of 1,737 was obtained with 23 dB extinction ratio. With stacked double-layer photonic crystal configuration, the optical filter Q can increase to over 10,000,000 in design. Double-layer filters with quality factor of 9,734 and extinction ratio of 8 dB were experimentally demonstrated, for a filter design with target Q of 22,000.

    View details for DOI 10.1364/OE.21.024582

    View details for Web of Science ID 000326085600016

    View details for PubMedID 24150302

  • Broadband Sharp 90-degree Bends and T-Splitters in Plasmonic Coaxial Waveguides. Nano letters Shin, W., Cai, W., Catrysse, P. B., Veronis, G., Brongersma, M. L., Fan, S. 2013; 13 (10): 4753-4758

    Abstract

    We demonstrate numerically that sharp 90° bends and T-splitters can be designed in plasmonic coaxial waveguides at deep-subwavelength scale to operate without reflection and radiation over a broad range of wavelengths, including the telecommunication wavelength of 1.55 μm. We explain the principles of the operation using a transmission line model of the waveguide in the quasi-static limit. The compact bends and T-splitters open up a new avenue for the design of densely integrated optical circuits with minimal crosstalk.

    View details for DOI 10.1021/nl402335x

    View details for PubMedID 23981038

  • Dissipation in few-photon waveguide transport [Invited] PHOTONICS RESEARCH Rephaeli, E., Fan, S. 2013; 1 (3): 110-114
  • Three-dimensional self-assembled photonic crystals with high temperature stability for thermal emission modification NATURE COMMUNICATIONS Arpin, K. A., Losego, M. D., Cloud, A. N., Ning, H., Mallek, J., Sergeant, N. P., Zhu, L., Yu, Z., Kalanyan, B., Parsons, G. N., Girolami, G. S., Abelson, J. R., Fan, S., Braun, P. V. 2013; 4

    Abstract

    Selective thermal emission in a useful range of energies from a material operating at high temperatures is required for effective solar thermophotovoltaic energy conversion. Three-dimensional metallic photonic crystals can exhibit spectral emissivity that is modified compared with the emissivity of unstructured metals, resulting in an emission spectrum useful for solar thermophotovoltaics. However, retention of the three-dimensional mesostructure at high temperatures remains a significant challenge. Here we utilize self-assembled templates to fabricate high-quality tungsten photonic crystals that demonstrate unprecedented thermal stability up to at least 1,400 °C and modified thermal emission at solar thermophotovoltaic operating temperatures. We also obtain comparable thermal and optical results using a photonic crystal comprising a previously unstudied material, hafnium diboride, suggesting that refractory metallic ceramic materials are viable candidates for photonic crystal-based solar thermophotovoltaic devices and should be more extensively studied.

    View details for DOI 10.1038/ncomms3630

    View details for Web of Science ID 000326472200019

    View details for PubMedID 24129680

  • Accelerated solution of the frequency-domain Maxwell's equations by engineering the eigenvalue distribution of the operator OPTICS EXPRESS Shin, W., Fan, S. 2013; 21 (19): 22578-22595

    Abstract

    We introduce a simple method to accelerate the convergence of iterative solvers of the frequency-domain Maxwell's equations for deep-subwavelength structures. Using the continuity equation, the method eliminates the high multiplicity of near-zero eigenvalues of the operator while leaving the operator nearly positive-definite. The impact of the modified eigenvalue distribution on the accelerated convergence is explained by visualizing residual vectors and residual polynomials.

    View details for DOI 10.1364/OE.21.022578

    View details for Web of Science ID 000325547200082

    View details for PubMedID 24104147

  • Large-area free-standing ultrathin single-crystal silicon as processable materials. Nano letters Wang, S., Weil, B. D., Li, Y., Wang, K. X., Garnett, E., Fan, S., Cui, Y. 2013; 13 (9): 4393-4398

    Abstract

    Silicon has been driving the great success of semiconductor industry, and emerging forms of silicon have generated new opportunities in electronics, biotechnology, and energy applications. Here we demonstrate large-area free-standing ultrathin single-crystalline Si at the wafer scale as new Si materials with processability. We fabricated them by KOH etching of the Si wafer and show their uniform thickness from 10 to sub-2 μm. These ultrathin Si exhibits excellent mechanical flexibility and bendability more than those with 20-30 μm thickness in previous study. Unexpectedly, these ultrathin Si materials can be cut with scissors like a piece of paper, and they are robust during various regular fabrication processings including tweezer handling, spin coating, patterning, doping, wet and dry etching, annealing, and metal deposition. We demonstrate the fabrication of planar and double-sided nanocone solar cells and highlight that the processability on both sides of surface together with the interesting property of these free-standing ultrathin Si materials opens up exciting opportunities to generate novel functional devices different from the existing approaches.

    View details for DOI 10.1021/nl402230v

    View details for PubMedID 23876030

  • Optical pulling force and conveyor belt effect in resonator-waveguide system OPTICS LETTERS Intaraprasonk, V., Fan, S. 2013; 38 (17): 3264-3267

    Abstract

    We present the theoretical condition and actual numerical design that achieves an optical pulling force in resonator-waveguide systems, where the direction of the force on the resonator is in the opposite direction to the input light in the waveguide. We also show that this pulling force can occur in conjunction with the lateral optical equilibrium effect, such that the resonator is maintained at the fixed distance from the waveguide while experiencing the pulling force.

    View details for DOI 10.1364/OL.38.003264

    View details for Web of Science ID 000323758000019

    View details for PubMedID 23988930

  • What is - and what is not - an optical isolator NATURE PHOTONICS Jalas, D., Petrov, A., Eich, M., Freude, W., Fan, S., Yu, Z., Baets, R., Popovic, M., Melloni, A., Joannopoulos, J. D., Vanwolleghem, M., Doerr, C. R., Renner, H. 2013; 7 (8): 579-582
  • Photonic de Haas-van Alphen effect OPTICS EXPRESS Fang, K., Yu, Z., Fan, S. 2013; 21 (15): 18216-18224

    Abstract

    Based on the recently proposed concept of effective gauge potential and magnetic field for photons, we numerically demonstrate a photonic de Haas-van Alphen effect. We show that in a dynamically modulated photonic resonator lattice exhibiting an effect magnetic field, the trajectories of the light beam at a given frequency have the same shape as the constant energy contour for the photonic band structure of the lattice in the absence of the effective magnetic field.

    View details for DOI 10.1364/OE.21.018216

    View details for Web of Science ID 000322366300081

    View details for PubMedID 23938692

  • Modeling Coherent Backscattering Errors in Fiber Optic Gyroscopes for Sources of Arbitrary Line Width JOURNAL OF LIGHTWAVE TECHNOLOGY Lloyd, S. W., Digonnet, M. J., Fan, S. 2013; 31 (13): 2070-2078
  • Experimental Observation of Low Noise and Low Drift in a Laser-Driven Fiber Optic Gyroscope JOURNAL OF LIGHTWAVE TECHNOLOGY Lloyd, S. W., Fan, S., Digonnet, M. J. 2013; 31 (13): 2079-2085
  • Slow-Light Fiber-Bragg-Grating Strain Sensor With a 280-femtostrain/root Hz Resolution JOURNAL OF LIGHTWAVE TECHNOLOGY Wen, H., Skolianos, G., Fan, S., Bernier, M., Vallee, R., Digonnet, M. J. 2013; 31 (11): 1804-1808
  • Wireless power transfer in the presence of metallic plates: Experimental results AIP ADVANCES Yu, X., Skauli, T., Skauli, B., Sandhu, S., Catrysse, P. B., Fan, S. 2013; 3 (6)

    View details for DOI 10.1063/1.4809665

    View details for Web of Science ID 000321144300002

  • A transparent electrode based on a metal nanotrough network. Nature nanotechnology Wu, H., Kong, D., Ruan, Z., Hsu, P., Wang, S., Yu, Z., Carney, T. J., Hu, L., Fan, S., Cui, Y. 2013; 8 (6): 421-425

    Abstract

    Transparent conducting electrodes are essential components for numerous flexible optoelectronic devices, including touch screens and interactive electronics. Thin films of indium tin oxide-the prototypical transparent electrode material-demonstrate excellent electronic performances, but film brittleness, low infrared transmittance and low abundance limit suitability for certain industrial applications. Alternatives to indium tin oxide have recently been reported and include conducting polymers, carbon nanotubes and graphene. However, although flexibility is greatly improved, the optoelectronic performance of these carbon-based materials is limited by low conductivity. Other examples include metal nanowire-based electrodes, which can achieve sheet resistances of less than 10Ω □(-1) at 90% transmission because of the high conductivity of the metals. To achieve these performances, however, metal nanowires must be defect-free, have conductivities close to their values in bulk, be as long as possible to minimize the number of wire-to-wire junctions, and exhibit small junction resistance. Here, we present a facile fabrication process that allows us to satisfy all these requirements and fabricate a new kind of transparent conducting electrode that exhibits both superior optoelectronic performances (sheet resistance of ∼2Ω □(-1) at 90% transmission) and remarkable mechanical flexibility under both stretching and bending stresses. The electrode is composed of a free-standing metallic nanotrough network and is produced with a process involving electrospinning and metal deposition. We demonstrate the practical suitability of our transparent conducting electrode by fabricating a flexible touch-screen device and a transparent conducting tape.

    View details for DOI 10.1038/nnano.2013.84

    View details for PubMedID 23685985

  • Near-infrared surface plasmon polariton dispersion control with hyperbolic metamaterials OPTICS EXPRESS Luk, T. S., Kim, I., Campione, S., Howell, S. W., Subramania, G. S., Grubbs, R. K., Brener, I., Chen, H., Fan, S., Sinclair, M. B. 2013; 21 (9): 11107-11114

    Abstract

    We demonstrate experimentally signatures and dispersion control of surface plasmon polaritons from 1 to 1.8 µm using periodic multilayer metallo-dielectric hyperbolic metamaterials. The fabricated structures are comprised of smooth films with very low metal filling factor. The measured dispersion properties of these hyperbolic metamaterials agree well with calculations using transfer matrix, finite-difference time-domain, and effective medium approximation methods despite using only 2.5 periods. The enhancement factor in the local photonic density of states from the studied samples in the near-infrared wavelength region is determined to be 2.5-3.5. Development of this type of metamaterial is relevant to sub-wavelength imaging, spontaneous emission and thermophotovoltaic applications.

    View details for DOI 10.1364/OE.21.011107

    View details for Web of Science ID 000318906500099

    View details for PubMedID 23669967

  • Upper bound on the modal material loss rate in plasmonic and metamaterial systems. Physical review letters Raman, A., Shin, W., Fan, S. 2013; 110 (18): 183901-?

    Abstract

    A better understanding of optical loss in plasmonic and metamaterial systems is of increasing importance for both basic and applied research in a broad range of topics including sensors, antennas, optical interconnects, and photovoltaics. In this Letter, we use a photonic band formalism for plasmonics to exactly derive a fundamental upper bound on the nonradiative material loss rate of modes in plasmonic, polaritonic, and metamaterial systems. This bound is purely defined by material properties and cannot be overcome by device design. Moreover it is frequency dependent in the presence of multiple Lorentz poles. We numerically verify this bound through direct calculations for a range of plasmonic systems, including optical antennas where the bound places fundamental performance constraints.

    View details for PubMedID 23683195

  • Resonant cavity enhanced light harvesting in flexible thin-film organic solar cells OPTICS LETTERS Sergeant, N. P., Niesen, B., Liu, A. S., Boman, L., Stoessel, C., Heremans, P., Peumans, P., Rand, B. P., Fan, S. 2013; 38 (9): 1431-1433

    Abstract

    Dielectric/metal/dielectric (DMD) electrodes have the potential to significantly increase the absorption efficiency and photocurrent in flexible organic solar cells. We demonstrate that this enhancement is attributed to a broadband cavity resonance. Silver-based semitransparent DMD electrodes with sheet resistances below 10 ohm/sq. are fabricated on flexible polyethylene terephthalate (PET) substrates in a high-throughput roll-to-roll sputtering tool. We carefully study the effect of the semitransparent DMD electrode (here composed of Zn(x)Sn(y)O(z)/Ag/In(x)Sn(y)O(z)) on the optical device performance of a copper phthalocyanine (CuPc)/fullerene (C60) bilayer cell and illustrate that a resonant cavity enhanced light trapping effect dominates the optical behavior of the device.

    View details for DOI 10.1364/OL.38.001431

    View details for Web of Science ID 000318425600024

    View details for PubMedID 23632508

  • Modal Source Radiator Model for Arbitrary Two-Dimensional Arrays of Subwavelength Apertures on Metal Films IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS Tanemura, T., Wahl, P., Fan, S., Miller, D. A. 2013; 19 (3)
  • Upper Bound on the Modal Material Loss Rate in Plasmonic and Metamaterial Systems PHYSICAL REVIEW LETTERS Raman, A., Shin, W., Fan, S. 2013; 110 (18)

    Abstract

    A better understanding of optical loss in plasmonic and metamaterial systems is of increasing importance for both basic and applied research in a broad range of topics including sensors, antennas, optical interconnects, and photovoltaics. In this Letter, we use a photonic band formalism for plasmonics to exactly derive a fundamental upper bound on the nonradiative material loss rate of modes in plasmonic, polaritonic, and metamaterial systems. This bound is purely defined by material properties and cannot be overcome by device design. Moreover it is frequency dependent in the presence of multiple Lorentz poles. We numerically verify this bound through direct calculations for a range of plasmonic systems, including optical antennas where the bound places fundamental performance constraints.

    View details for DOI 10.1103/PhysRevLett.110.183901

    View details for Web of Science ID 000319014400001

    View details for PubMedID 23683195

  • Compact bends for multi-mode photonic crystal waveguides with high transmission and suppressed modal crosstalk OPTICS EXPRESS Liu, V., Fan, S. 2013; 21 (7): 8069-8075

    Abstract

    We demonstrate an extremely compact bend for a photonic crystal waveguide supporting three spatial modes. The bend exhibits nearly 100% transmission over a relative bandwidth of 1% with less than 1% crosstalk. We show that our design is robust with respect to fabrication errors. Our design method is applied to create a structure consisting of dielectric rods, as well as a structure consisting of air holes in a dielectric background.

    View details for Web of Science ID 000317659300023

    View details for PubMedID 23571897

  • Ultrabroadband Photonic Structures To Achieve High-Performance Daytime Radiative Cooling NANO LETTERS Rephaeli, E., Raman, A., Fan, S. 2013; 13 (4): 1457-1461

    Abstract

    If properly designed, terrestrial structures can passively cool themselves through radiative emission of heat to outer space. For the first time, we present a metal-dielectric photonic structure capable of radiative cooling in daytime outdoor conditions. The structure behaves as a broadband mirror for solar light, while simultaneously emitting strongly in the mid-IR within the atmospheric transparency window, achieving a net cooling power in excess of 100 W/m(2) at ambient temperature. This cooling persists in the presence of significant convective/conductive heat exchange and nonideal atmospheric conditions.

    View details for DOI 10.1021/nl4004283

    View details for Web of Science ID 000317549300016

    View details for PubMedID 23461597

  • Experimental Assessment of the Accuracy of an Advanced Photonic-Bandgap-Fiber Model JOURNAL OF LIGHTWAVE TECHNOLOGY Aghaie, K. Z., Digonnet, M. J., Fan, S. 2013; 31 (7): 1015-1022
  • Fluorescence Correlation Spectroscopy at High Concentrations using Gold Bowtie Nanoantennas (vol 406C, pg 3, 2012) CHEMICAL PHYSICS Kinkhabwala, A. A., Yu, Z., Fan, S., Moerner, E. 2013; 415: 309-309
  • Temporal coupled mode theory for thermal emission from a single thermal emitter supporting either a single mode or an orthogonal set of modes APPLIED PHYSICS LETTERS Zhu, L., Sandhu, S., Otey, C., Fan, S., Sinclair, M. B., Luk, T. S. 2013; 102 (10)

    View details for DOI 10.1063/1.4794981

    View details for Web of Science ID 000316501200067

  • Experimental demonstration of a photonic Aharonov-Bohm effect at radio frequencies PHYSICAL REVIEW B Fang, K., Yu, Z., Fan, S. 2013; 87 (6)
  • Highly Tailored Computational Electromagnetics Methods for Nanophotonic Design and Discovery PROCEEDINGS OF THE IEEE Liu, V., Miller, D. A., Fan, S. 2013; 101 (2): 484-493
  • Transparent and conductive paper from nanocellulose fibers ENERGY & ENVIRONMENTAL SCIENCE Hu, L., Zheng, G., Yao, J., Liu, N., Weil, B., Eskilsson, M., Karabulut, E., Ruan, Z., Fan, S., Bloking, J. T., McGehee, M. D., Wagberg, L., Cui, Y. 2013; 6 (2): 513-518

    View details for DOI 10.1039/c2ee23635d

    View details for Web of Science ID 000313892400013

  • Tight-binding calculation of radiation loss in photonic crystal CROW OPTICS EXPRESS Ma, J., Martinez, L. J., Fan, S., Povinelli, M. L. 2013; 21 (2): 2463-2473

    Abstract

    The tight binding approximation (TBA) is used to relate the intrinsic, radiation loss of a coupled resonator optical waveguide (CROW) to that of a single constituent resonator within a light cone picture. We verify the validity of the TBA via direct, full-field simulation of CROWs based on the L2 photonic crystal cavity. The TBA predicts that the quality factor of the CROW increases with that of the isolated cavity. Moreover, our results provide a method to design CROWs with low intrinsic loss across the entire waveguide band.

    View details for Web of Science ID 000315989500110

    View details for PubMedID 23389227

  • Fundamental bounds on decay rates in asymmetric single-mode optical resonators OPTICS LETTERS Wang, K. X., Yu, Z., Sandhu, S., Fan, S. 2013; 38 (2): 100-102

    Abstract

    We derive tight upper and lower bounds of the ratio between decay rates to two ports from a single resonance exhibiting Fano interference, based on a general temporal coupled-mode theory formalism. The photon transport between these two ports involves both direct and resonance-assisted contributions, and the bounds depend only on the direct process. The bounds imply that, in a lossless system, full reflection is always achievable at Fano resonance, even for structures lacking mirror symmetries, while full transmission can only be seen in a symmetric configuration where the two decay rates are equal. The analytic predictions are verified against full-field electromagnetic simulations.

    View details for Web of Science ID 000313636600007

    View details for PubMedID 23454928

  • Detailed balance analysis of nanophotonic solar cells OPTICS EXPRESS Sandhu, S., Yu, Z., Fan, S. 2013; 21 (1): 1209-1217

    Abstract

    We present a detailed balance based approach for performing current density-voltage characteristic modeling of nanophotonic solar cells. This approach takes into account the intrinsic material non-idealities, and is useful for determining the theoretical limit of solar cell efficiency for a given structure. Our approach only requires the cell's absorption spectra over all angles, which can be readily calculated using available simulation tools. Using this approach, we elucidate the physics of open-circuit voltage enhancement over bulk cells in nanoscale thin film structures, by showing that the enhancement is related to the absorption suppression in the immediate spectral region above the bandgap. We also show that with proper design, the use of a grating on a nanoscale thin film can increase its short-circuit current, while preserving its voltage-enhancing capabilities.

    View details for Web of Science ID 000315988100144

    View details for PubMedID 23389013

  • Routing of Deep-Subwavelength Optical Beams and Images without Reflection and Diffraction Using Infinitely Anisotropic Metamaterials ADVANCED MATERIALS Catrysse, P. B., Fan, S. 2013; 25 (2): 194-198

    Abstract

    Interfaces between media with infinite anisotropy, defined by infinite permittivity or permeability in one direction, offer new opportunities for controlling and manipulating light at the nanoscale. Reflectionless, diffraction-free routing of deep-subwavelength optical beams and images using interfaces between infinitely anisotropic media are demonstrated. It is shown how to achieve extremely large anisotropy using metamaterial designs that can be implemented with existing materials.

    View details for DOI 10.1002/adma.201203528

    View details for Web of Science ID 000313262300005

    View details for PubMedID 23180728

  • Synthetic magnetic field directs photons PHOTONICS SPECTRA Fan, S. 2013; 47 (1): 28-?
  • Limits on nanophotonic solar cell light trapping in the presence of parasitic losses Raman, A., Fan, S., IEEE IEEE. 2013
  • Enhancing far-field thermal emission with thermal extraction Yu, Z., Sergeant, N., Skauli, T., Zhang, G., Wang, H., Fan, S., IEEE IEEE. 2013
  • Dispersion control of near-infrared surface plasmon polariton using hyperbolic metamaterials Kim, I., Campione, S., Howell, S. W., Subramania, G. S., Grubbs, R. K., Brener, I., Chen, H., Fan, S., Sinclair, M. B., Luk, T. S., IEEE IEEE. 2013
  • Temporal Coupled mode theory for thermal emission from a single emitter Zhu, L., Sandhu, S., Otey, C., Sinclair, M. B., Luk, T., Fan, S., IEEE IEEE. 2013
  • Broadband Management of Light Using Nanophotonics for Solar and Thermal Applications Fan, S., IEEE IEEE. 2013
  • Transfer Printed Nanomembrane High-Q Filters Based on Displaced Double-Layer Fano Resonance Photonic Crystal Slabs Shuai, Y., Zhao, D., Seo, J., Yang, H., Fan, S., Ma, Z., Zhou, W., IEEE IEEE. 2013: 444-445
  • Plasmonic nano-coaxial waveguides for 90-degree bends and T-splitters Shin, W., Cai, W., Catrysse, P. B., Veronis, G., Brongersma, M. L., Fan, S., IEEE IEEE. 2013
  • Inducing Electro-Optic Photonic Transitions for Enabling Isolation in Silicon Photonics IEEE-Photonics-Society Summer Topical Meeting Tzuang, L., Poitras, C. B., Lipson, M., Fang, K., Fan, S., Nussenzveig, P. A. IEEE. 2013: 205–205
  • Large-Area Free-Standing Ultrathin Single-Crystal Silicon as Processable Materials Nano Letters Wang, S., Weil, B., Li, Y., Wang, K., X., Garnett, E., Fan, S., Cui, Y. 2013: 4393–98

    Abstract

    Silicon has been driving the great success of semiconductor industry, and emerging forms of silicon have generated new opportunities in electronics, biotechnology, and energy applications. Here we demonstrate large-area free-standing ultrathin single-crystalline Si at the wafer scale as new Si materials with processability. We fabricated them by KOH etching of the Si wafer and show their uniform thickness from 10 to sub-2 μm. These ultrathin Si exhibits excellent mechanical flexibility and bendability more than those with 20-30 μm thickness in previous study. Unexpectedly, these ultrathin Si materials can be cut with scissors like a piece of paper, and they are robust during various regular fabrication processings including tweezer handling, spin coating, patterning, doping, wet and dry etching, annealing, and metal deposition. We demonstrate the fabrication of planar and double-sided nanocone solar cells and highlight that the processability on both sides of surface together with the interesting property of these free-standing ultrathin Si materials opens up exciting opportunities to generate novel functional devices different from the existing approaches.

    View details for DOI 10.1021/nl402230v

  • Tight-binding calculation of radiation loss in photonic crystal CROW Ma, J., Martinez, L., Fan, S., Povinelli, M. L., IEEE IEEE. 2013
  • Optimization of non-periodic plasmonic light-trapping layers for thin-film solar cells. Nature communications Pala, R. A., Liu, J. S., Barnard, E. S., Askarov, D., Garnett, E. C., Fan, S., Brongersma, M. L. 2013; 4: 2095-?

    Abstract

    Non-periodic arrangements of nanoscale light scatterers allow for the realization of extremely effective broadband light-trapping layers for solar cells. However, their optimization is challenging given the massive number of degrees of freedom. Brute-force, full-field electromagnetic simulations are computationally too time intensive to identify high-performance solutions in a vast design space. Here we illustrate how a semi-analytical model can be used to quickly identify promising non-periodic spatial arrangements of nanoscale scatterers. This model only requires basic knowledge of the scattering behaviour of a chosen nanostructure and the waveguiding properties of the semiconductor layer in a cell. Due to its simplicity, it provides new intuition into the ideal amount of disorder in high-performance light-trapping layers. Using simulations and experiments, we demonstrate that arrays of nanometallic stripes featuring a limited amount of disorder, for example, following a quasi-periodic or Fibonacci sequence, can substantially enhance solar absorption over perfectly periodic and random arrays.

    View details for DOI 10.1038/ncomms3095

    View details for PubMedID 23817445

  • Optimization of non-periodic plasmonic light-trapping layers for thin-film solar cells. Nature communications Pala, R. A., Liu, J. S., Barnard, E. S., Askarov, D., Garnett, E. C., Fan, S., Brongersma, M. L. 2013; 4: 2095-?

    View details for DOI 10.1038/ncomms3095

    View details for PubMedID 23817445

  • Modeling Loss and Backscattering in a Photonic-Bandgap Fiber Using Strong Perturbation Conference on Photonic and Phononic Properties of Engineered Nanostructures III Aghaie, K. Z., Digonnet, M. J., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2013

    View details for DOI 10.1117/12.2006446

    View details for Web of Science ID 000322962900014

  • Photonic structures: advanced thermal control, and effective gauge field for light 7th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics (METAMATERIALS) Fan, S., Yu, Z., Fang, K., Rephaeli, E., Raman, A. IEEE. 2013: 232–233
  • Manipulating Thermal Electromagnetic Fields by Engineering Nanophotonic Resonances 10th Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR) Fan, S., Yu, Z., Rephaeli, E., Raman, A. IEEE. 2013
  • Local density of states of chiral Hall edge states in gyrotropic photonic clusters Physical Review B Fan, S., H., Asatryan, A., A., Botten, L., C., Fang et. al., K., J. 2013; 88 (3)
  • Color-preserving daytime radiative cooling Applied Physics Letters Zhu, L., X., Raman, A., Fan, S., H. 2013; 103 (22)

    View details for DOI 10.1063/1.4835995

  • Effective magnetic field for photons based on the magneto-optical effect Physical Review A Fang, K., J., Fan, S., H. 2013; 88 (4)
  • Deep subwavelength plasmonic waveguide switch in double graphene layer structure Applied Physics Letters Iizuka, H., Fan, S., H. 2013; 103 (23)

    View details for DOI 10.1063/1.4839420

  • What is - and what is not - an optical isolator Nature Photonics Fan, S., H., Jalas, D., Petrov, A., Eich et. al., M. 2013; 7 (8): 579-582

    View details for DOI 10.1038/nphoton.2013.185

  • Upper Bound on the Modal Material Loss Rate in Plasmonic and Metamaterial Systems Physical Review Letters Raman, A., Shin, W., Fan, S., H. 2013; 110 (18)
  • Two-photon transport through a waveguide coupling to a whispering-gallery resonator containing an atom and photon-blockade effect Physical Review A Shi, T., Fan, S., H. 2013; 87 (6)
  • Two-Dimensional Chalcogenide Nanoplates as Tunable Metamaterials via Chemical Intercalation Nano Letters Fan, S., H., Cha, J., J., Koski, K., J., Huang et al., K., C. Y. 2013; 13 (12): 5913-5918

    View details for DOI 10.1021/nl402937g

  • Metamaterial band theory: fundamentals & applications Science China-Information Sciences Raman, A., P., Shin, W., Fan, S., H. 2013; 56 (12)
  • Experimental demonstration of a photonic Aharonov-Bohm effect at radio frequencies Physical Review B Fang, K., J., Yu, Z., F., Fan, S., H. 2013; 87 (6)
  • Coupled double-layer Fano resonance photonic crystal filters with lattice-displacement Applied Physics Letters Fan, S., H., Shuai, Y., C., Zhao, D., Y., Chadha et al, A., S. 2013; 103 (24)

    View details for DOI 10.1063/1.4846475

  • Analytic Properties of Two-Photon Scattering Matrix in Integrated Quantum Systems Determined by the Cluster Decomposition Principle Physical Review Letters Xu, S., S., Rephaeli, E., Fan, S., H. 2013; 111 (22)
  • Enhancing far-field thermal emission with thermal extraction Nature Communications Fan, S., H., Yu, Z., Sergeant, N., P., Skauli et al., T. 2013; 4

    View details for DOI 10.1038/ncomms2765

  • Ultrahigh-contrast and large-bandwidth thermal rectification in near-field electromagnetic thermal transfer between nanoparticles Physical Review B Zhu, L., X., Otey, C., R., Fan, S., H. 2013; 88 (18)
  • Three-dimensional self-assembled photonic crystals with high temperature stability for thermal emission modification Nature Communications Fan, S., H., Arpin, K., A., Losego, M., D., Cloud et. al., A., N. 2013; 4

    View details for DOI 10.1038/ncomms3630

  • Fluorescence Correlation Spectroscopy at High Concentrations using Gold Bowtie Nanoantennas (vol 406C, pg 3, 2012) Chemical Physics Kinkhabwala, A., A., Yu, Z., F., Fan et. al., S., H. 2013; 415: 309
  • Controlling the Flow of Light Using the Inhomogeneous Effective Gauge Field that Emerges from Dynamic Modulation Physical Review Letters Fang, K., J., Fan, S., H. 2013; 111 (20)
  • Wireless power transfer in the presence of metallic plates: Experimental results Aip Advances Fan, S., H., Yu, X., F., Skauli, T., Skauli et. al., B. 2013; 3 (6)

    View details for DOI 10.1063/1.4809665

  • Temporal coupled mode theory for thermal emission from a single thermal emitter supporting either a single mode or an orthogonal set of modes Applied Physics Letters Fan, S., H., Zhu, L., X., Sandhu, S., Otey et. al., C. 2013; 102 (10)

    View details for DOI 10.1063/1.4794981

  • Optimization of non-periodic plasmonic light-trapping layers for thin-film solar cells Nature Communications Fan, S., H., Pala, R., A., Liu, J., S. Q., Barnard et. al., E., S. 2013; 4

    View details for DOI 10.1038/ncomms3095

  • Modal Source Radiator Model for Arbitrary Two-Dimensional Arrays of Subwavelength Apertures on Metal Films Ieee Journal of Selected Topics in Quantum Electronics Tanemura, T., Wahl, P., Fan et. al., S., H. 2013; 19 (3)
  • A transparent electrode based on a metal nanotrough network Nature Nanotechnology Fan, S., H., Wu, H., Kong, S., D., Ruan et al., C., Z. 2013; 8 (6): 421-425

    Abstract

    Transparent conducting electrodes are essential components for numerous flexible optoelectronic devices, including touch screens and interactive electronics. Thin films of indium tin oxide-the prototypical transparent electrode material-demonstrate excellent electronic performances, but film brittleness, low infrared transmittance and low abundance limit suitability for certain industrial applications. Alternatives to indium tin oxide have recently been reported and include conducting polymers, carbon nanotubes and graphene. However, although flexibility is greatly improved, the optoelectronic performance of these carbon-based materials is limited by low conductivity. Other examples include metal nanowire-based electrodes, which can achieve sheet resistances of less than 10Ω □(-1) at 90% transmission because of the high conductivity of the metals. To achieve these performances, however, metal nanowires must be defect-free, have conductivities close to their values in bulk, be as long as possible to minimize the number of wire-to-wire junctions, and exhibit small junction resistance. Here, we present a facile fabrication process that allows us to satisfy all these requirements and fabricate a new kind of transparent conducting electrode that exhibits both superior optoelectronic performances (sheet resistance of ∼2Ω □(-1) at 90% transmission) and remarkable mechanical flexibility under both stretching and bending stresses. The electrode is composed of a free-standing metallic nanotrough network and is produced with a process involving electrospinning and metal deposition. We demonstrate the practical suitability of our transparent conducting electrode by fabricating a flexible touch-screen device and a transparent conducting tape.

    View details for DOI 10.1038/nnano.2013.84

  • Broadband Sharp 90-degree Bends and T-Splitters in Plasmonic Coaxial Waveguides Nano Letters Fan, S., H., Shin, W., Cai, W., S., Catrysse et al., P., B. 2013; 13 (10): 4753-4758

    Abstract

    We demonstrate numerically that sharp 90° bends and T-splitters can be designed in plasmonic coaxial waveguides at deep-subwavelength scale to operate without reflection and radiation over a broad range of wavelengths, including the telecommunication wavelength of 1.55 μm. We explain the principles of the operation using a transmission line model of the waveguide in the quasi-static limit. The compact bends and T-splitters open up a new avenue for the design of densely integrated optical circuits with minimal crosstalk.

    View details for DOI 10.1021/nl402335x

  • Enhancing far-field thermal emission with thermal extraction. Nature communications Yu, Z., Sergeant, N. P., Skauli, T., Zhang, G., Wang, H., Fan, S. 2013; 4: 1730-?

    Abstract

    The control of thermal radiation is of great current importance for applications such as energy conversions and radiative cooling. Here we show theoretically that the thermal emission of a finite-size blackbody emitter can be enhanced in a thermal extraction scheme, where one places the emitter in optical contact with an extraction device consisting of a transparent object, as long as both the emitter and the extraction device have an internal density of state higher than vacuum, and the extraction device has an area larger than the emitter and moreover has a geometry that enables light extraction. As an experimental demonstration of the thermal extraction scheme, we observe a four-fold enhancement of the far-field thermal emission of a carbon-black emitter having an emissivity of 0.85.

    View details for DOI 10.1038/ncomms2765

    View details for PubMedID 23591897

  • Enhancing the waveguide-resonator optical force with an all-optical on-chip analog of electromagnetically induced transparency PHYSICAL REVIEW A Intaraprasonk, V., Fan, S. 2012; 86 (6)
  • Ultra-compact photonic crystal waveguide spatial mode converter and its connection to the optical diode effect OPTICS EXPRESS Liu, V., Miller, D. A., Fan, S. 2012; 20 (27): 28388-28397

    Abstract

    We design an extremely compact photonic crystal waveguide spatial mode converter which converts the fundamental even mode to the higher order odd mode with nearly 100% efficiency. We adapt a previously developed design and optimization process that allows these types of devices to be designed in a matter of minutes. We also present an extremely compact optical diode device and clarify its general properties and its relation to spatial mode converters. Finally, we connect the results here to a general theory on the complexity of optical designs.

    View details for PubMedID 23263074

  • A simple Bayesian decision-theoretic design for dose-finding trials STATISTICS IN MEDICINE Fan, S. K., Lu, Y., Wang, Y. 2012; 31 (28): 3719-3730

    Abstract

    A flexible and simple Bayesian decision-theoretic design for dose-finding trials is proposed in this paper. In order to reduce the computational burden, we adopt a working model with conjugate priors, which is flexible to fit all monotonic dose-toxicity curves and produces analytic posterior distributions. We also discuss how to use a proper utility function to reflect the interest of the trial. Patients are allocated based on not only the utility function but also the chosen dose selection rule. The most popular dose selection rule is the one-step-look-ahead (OSLA), which selects the best-so-far dose. A more complicated rule, such as the two-step-look-ahead, is theoretically more efficient than the OSLA only when the required distributional assumptions are met, which is, however, often not the case in practice. We carried out extensive simulation studies to evaluate these two dose selection rules and found that OSLA was often more efficient than two-step-look-ahead under the proposed Bayesian structure. Moreover, our simulation results show that the proposed Bayesian method's performance is superior to several popular Bayesian methods and that the negative impact of prior misspecification can be managed in the design stage.

    View details for DOI 10.1002/sim.5438

    View details for Web of Science ID 000311402300021

    View details for PubMedID 22763943

  • On the Time to Conclusion of Phase II Cancer Clinical Trials and Its Application in Trial Designs STATISTICS IN BIOPHARMACEUTICAL RESEARCH 2012; 4 (4): 324-335
  • Realizing effective magnetic field for photons by controlling the phase of dynamic modulation NATURE PHOTONICS Fang, K., Yu, Z., Fan, S. 2012; 6 (11): 782-787
  • Few-Photon Single-Atom Cavity QED With Input-Output Formalism in Fock Space IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS Rephaeli, E., Fan, S. 2012; 18 (6): 1754-1762
  • Thermodynamic Upper Bound on Broadband Light Coupling with Photonic Structures PHYSICAL REVIEW LETTERS Yu, Z., Raman, A., Fan, S. 2012; 109 (17)

    Abstract

    The coupling between free space radiation and optical media critically influences the performance of optical devices. We show that, for any given photonic structure, the sum of the external coupling rates for all its optical modes are subject to an upper bound dictated by the second law of thermodynamics. Such bound limits how efficient light can be coupled to any photonic structure. As one example of application, we use this upper bound to derive the limit of light absorption in broadband solar absorbers.

    View details for DOI 10.1103/PhysRevLett.109.173901

    View details for Web of Science ID 000310200100011

    View details for PubMedID 23215189

  • Fluorescence correlation spectroscopy at high concentrations using gold bowtie nanoantennas CHEMICAL PHYSICS Kinkhabwala, A. A., Yu, Z., Fan, S., Moerner, W. E. 2012; 406: 3-8
  • Optical Absorption Enhancement in Freestanding GaAs Thin Film Nanopyramid Arrays ADVANCED ENERGY MATERIALS Liang, D., Huo, Y., Kang, Y., Wang, K. X., Gu, A., Tan, M., Yu, Z., Li, S., Jia, J., Bao, X., Wang, S., Yao, Y., Wong, H. P., Fan, S., Cui, Y., Harris, J. S. 2012; 2 (10): 1254-1260
  • S-4: A free electromagnetic solver for layered periodic structures COMPUTER PHYSICS COMMUNICATIONS Liu, V., Fan, S. 2012; 183 (10): 2233-2244
  • Design for broadband on-chip isolator using stimulated Brillouin scattering in dispersion-engineered chalcogenide waveguides OPTICS EXPRESS Poulton, C. G., Pant, R., Byrnes, A., Fan, S., Steel, M. J., Eggleton, B. J. 2012; 20 (19): 21235-21246

    Abstract

    We propose a scheme for on-chip isolation in chalcogenide (As₂S₃) rib waveguides, in which Stimulated Brillouin Scattering is used to induce non-reciprocal mode conversion within a multi-moded waveguide. The design exploits the idea that a chalcogenide rib buried in a silica matrix acts as waveguide for both light and sound, and can also be designed to be multi-moded for both optical and acoustic waves. The enhanced opto-acoustic coupling allows significant isolation (> 20 dB) within a chip-scale (cm-long) device (< 10 cm). We also show that the bandwidth of this device can be dramatically increased by tuning the dispersion of the waveguide to match the group velocity between optical modes: we find that 20 dB isolation can be extended over a bandwidth of 25 nm.

    View details for Web of Science ID 000308865600066

    View details for PubMedID 23037247

  • Near-Field Radiative Cooling of Nanostructures NANO LETTERS Guha, B., Otey, C., Poitras, C. B., Fan, S., Lipson, M. 2012; 12 (9): 4546-4550

    Abstract

    We measure near-field radiative cooling of a thermally isolated nanostructure up to a few degrees and show that in principle this process can efficiently cool down localized hotspots by tens of degrees at submicrometer gaps. This process of cooling is achieved without any physical contact, in contrast to heat transfer through conduction, thus enabling novel cooling capabilities. We show that the measured trend of radiative cooling agrees well theoretical predictions and is limited mainly by the geometry of the probe used here as well as the minimum separation that could be achieved in our setup. These results also pave the way for realizing other new effects based on resonant heat transfer, like thermal rectification and negative thermal conductance.

    View details for DOI 10.1021/nl301708e

    View details for Web of Science ID 000308576000021

    View details for PubMedID 22891815

  • Photonic chip based tunable and reconfigurable narrowband microwave photonic filter using stimulated Brillouin scattering OPTICS EXPRESS Byrnes, A., Pant, R., Li, E., Choi, D., Poulton, C. G., Fan, S., Madden, S., Luther-Davies, B., Eggleton, B. J. 2012; 20 (17): 18836-18845

    Abstract

    We report the first demonstration of a photonic chip based dynamically reconfigurable, widely tunable, narrow pass-band, high Q microwave photonic filter (MPF). We exploit stimulated Brillouin scattering (SBS) in a 6.5 cm long chalcogenide (As2S3) photonic chip to demonstrate a MPF that exhibited a high quality factor of ~520 and narrow bandwidth and was dynamically reconfigurable and widely tunable. It maintained a stable 3 dB bandwidth of 23 ± 2MHz and amplitude of 20 ± 2 dB over a large frequency tuning range of 2-12 GHz. By tailoring the pump spectrum, we reconfigured the 3 dB bandwidth of the MPF from ~20 MHz to ~40 MHz and tuned the shape factor from 3.5 to 2 resulting in a nearly flat-topped filter profile. This demonstration represents a significant advance in integrated microwave photonics with potential applications in on-chip microwave signal processing for RADAR and analogue communications.

    View details for Web of Science ID 000307873600033

    View details for PubMedID 23038523

  • Electrically Driven Nonreciprocity Induced by Interband Photonic Transition on a Silicon Chip PHYSICAL REVIEW LETTERS Lira, H., Yu, Z., Fan, S., Lipson, M. 2012; 109 (3)

    Abstract

    We demonstrate electrically driven nonreciprocity on a silicon chip. By achieving an indirect interband photonic transition, we show that the transmission coefficients between two single-mode waveguides become dependent on the propagation directions only in the presence of the electrical drive. Our structure is characterized by a nonsymmetric scattering matrix identical to a linear magneto-optical device.

    View details for DOI 10.1103/PhysRevLett.109.033901

    View details for Web of Science ID 000306417600002

    View details for PubMedID 22861851

  • Rectification of evanescent heat transfer between dielectric-coated and uncoated silicon carbide plates JOURNAL OF APPLIED PHYSICS Iizuka, H., Fan, S. 2012; 112 (2)

    View details for DOI 10.1063/1.4737465

    View details for Web of Science ID 000308424500087

  • Hybrid Silicon Nanocone-Polymer Solar Cells NANO LETTERS Jeong, S., Garnett, E. C., Wang, S., Yu, Z., Fan, S., Brongersma, M. L., McGehee, M. D., Cui, Y. 2012; 12 (6): 2971-2976

    Abstract

    Recently, hybrid Si/organic solar cells have been studied for low-cost Si photovoltaic devices because the Schottky junction between the Si and organic material can be formed by solution processes at a low temperature. In this study, we demonstrate a hybrid solar cell composed of Si nanocones and conductive polymer. The optimal nanocone structure with an aspect ratio (height/diameter of a nanocone) less than two allowed for conformal polymer surface coverage via spin-coating while also providing both excellent antireflection and light trapping properties. The uniform heterojunction over the nanocones with enhanced light absorption resulted in a power conversion efficiency above 11%. Based on our simulation study, the optimal nanocone structures for a 10 μm thick Si solar cell can achieve a short-circuit current density, up to 39.1 mA/cm(2), which is very close to the theoretical limit. With very thin material and inexpensive processing, hybrid Si nanocone/polymer solar cells are promising as an economically viable alternative energy solution.

    View details for DOI 10.1021/nl300713x

    View details for Web of Science ID 000305106400054

    View details for PubMedID 22545674

  • High-Efficiency Amorphous Silicon Solar Cell on a Periodic Nanocone Back Reflector ADVANCED ENERGY MATERIALS Hsu, C., Battaglia, C., Pahud, C., Ruan, Z., Haug, F., Fan, S., Ballif, C., Cui, Y. 2012; 2 (6): 628-633
  • Instantaneous electric energy and electric power dissipation in dispersive media JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS Shin, W., Raman, A., Fan, S. 2012; 29 (5): 1048-1054
  • Choice of the perfectly matched layer boundary condition for frequency-domain Maxwell's equations solvers JOURNAL OF COMPUTATIONAL PHYSICS Shin, W., Fan, S. 2012; 231 (8): 3406-3431
  • Temporal coupled-mode theory for light scattering by an arbitrarily shaped object supporting a single resonance PHYSICAL REVIEW A Ruan, Z., Fan, S. 2012; 85 (4)
  • Photonic Aharonov-Bohm Effect Based on Dynamic Modulation PHYSICAL REVIEW LETTERS Fang, K., Yu, Z., Fan, S. 2012; 108 (15)

    Abstract

    We show that when the refractive index of a photonic system is harmonically modulated, the phase of the modulation introduces an effective gauge potential for photons. This effective gauge potential can be used to create a photonic Aharonov-Bohm effect. We show that the photonic Aharonov-Bohm effect provides the optimal mechanism for achieving complete on-chip nonmagnetic optical isolation.

    View details for DOI 10.1103/PhysRevLett.108.153901

    View details for Web of Science ID 000302703600004

    View details for PubMedID 22587255

  • Stimulated Emission from a Single Excited Atom in a Waveguide PHYSICAL REVIEW LETTERS Rephaeli, E., Fan, S. 2012; 108 (14)

    Abstract

    We study stimulated emission from an excited two-level atom coupled to a waveguide containing an incident single-photon pulse. We show that the strong photon correlation, as induced by the atom, plays a very important role in stimulated emission. Additionally, the temporal duration of the incident photon pulse is shown to have a marked effect on stimulated emission and atomic lifetime.

    View details for DOI 10.1103/PhysRevLett.108.143602

    View details for Web of Science ID 000302293500010

    View details for PubMedID 22540793

  • Resonant Fiber Optic Gyroscope Using an Air-Core Fiber JOURNAL OF LIGHTWAVE TECHNOLOGY Terrel, M. A., Digonnet, M. J., Fan, S. 2012; 30 (7): 931-937
  • Absorption Enhancement in Ultrathin Crystalline Silicon Solar Cells with Antireflection and Light-Trapping Nanocone Gratings NANO LETTERS Wang, K. X., Yu, Z., Liu, V., Cui, Y., Fan, S. 2012; 12 (3): 1616-1619

    Abstract

    Enhancing the light absorption in ultrathin-film silicon solar cells is important for improving efficiency and reducing cost. We introduce a double-sided grating design, where the front and back surfaces of the cell are separately optimized for antireflection and light trapping, respectively. The optimized structure yields a photocurrent of 34.6 mA/cm(2) at an equivalent thickness of 2 μm, close to the Yablonovitch limit. This approach is applicable to various thicknesses and is robust against metallic loss in the back reflector.

    View details for DOI 10.1021/nl204550q

    View details for Web of Science ID 000301406800086

    View details for PubMedID 22356436

  • From Electromagnetically Induced Transparency to Superscattering with a Single Structure: A Coupled-Mode Theory for Doubly Resonant Structures PHYSICAL REVIEW LETTERS Verslegers, L., Yu, Z., Ruan, Z., Catrysse, P. B., Fan, S. 2012; 108 (8)

    Abstract

    We observe from simulations that a doubly resonant structure can exhibit spectral behavior analogous to electromagnetically induced transparency, as well as superscattering, depending on the excitation. We develop a coupled-mode theory that explains this behavior in terms of the orthogonality of the radiation patterns of the eigenmodes. These results provide insight in the general electromagnetic properties of photonic nanostructures and metamaterials.

    View details for DOI 10.1103/PhysRevLett.108.083902

    View details for Web of Science ID 000300576000010

    View details for PubMedID 22463532

  • Resonance fluorescence in a waveguide geometry PHYSICAL REVIEW A Kocabas, S. E., Rephaeli, E., Fan, S. 2012; 85 (2)
  • Lossless intensity modulation in integrated photonics OPTICS EXPRESS Sandhu, S., Fan, S. 2012; 20 (4): 4280-4290

    Abstract

    We present a dynamical analysis of lossless intensity modulation in two different ring resonator geometries. In both geometries, we demonstrate modulation schemes that result in a symmetrical output with an infinite on/off ratio. The systems behave as lossless intensity modulators where the time-averaged output optical power is equal to the time-averaged input optical power.

    View details for Web of Science ID 000301041900093

    View details for PubMedID 22418187

  • Broadband light management using low-Q whispering gallery modes in spherical nanoshells NATURE COMMUNICATIONS Yao, Y., Yao, J., Narasimhan, V. K., Ruan, Z., Xie, C., Fan, S., Cui, Y. 2012; 3

    Abstract

    Light trapping across a wide band of frequencies is important for applications such as solar cells and photodetectors. Here, we demonstrate a new approach to light management by forming whispering-gallery resonant modes inside a spherical nanoshell structure. The geometry of the structure gives rise to a low quality-factor, facilitating the coupling of light into the resonant modes and substantial enhancement of the light path in the active material, thus dramatically improving absorption. Using nanocrystalline silicon (nc-Si) as a model system, we observe broadband absorption enhancement across a large range of incident angles. The absorption of a single layer of 50-nm-thick spherical nanoshells is equivalent to a 1-μm-thick planar nc-Si film. This light-trapping structure could enable the manufacturing of high-throughput ultra-thin film absorbers in a variety of material systems that demand shorter deposition time, less material usage and transferability to flexible substrates.

    View details for DOI 10.1038/ncomms1664

    View details for PubMedID 22314360

  • Negative differential thermal conductance through vacuum APPLIED PHYSICS LETTERS Zhu, L., Otey, C. R., Fan, S. 2012; 100 (4)

    View details for DOI 10.1063/1.3679694

    View details for Web of Science ID 000300064500085

  • Comment on "Nonreciprocal Light Propagation in a Silicon Photonic Circuit" SCIENCE Fan, S., Baets, R., Petrov, A., Yu, Z., Joannopoulos, J. D., Freude, W., Melloni, A., Popovic, M., Vanwolleghem, M., Jalas, D., Eich, M., Krause, M., Renner, H., Brinkmeyer, E., Doerr, C. R. 2012; 335 (6064)

    Abstract

    We show that the structure demonstrated by Feng et al. (Reports, 5 August 2011, p. 729) cannot enable optical isolation because it possesses a symmetric scattering matrix. Moreover, one cannot construct an optical isolator by incorporating this structure into any system as long as the system is linear and time-independent and is described by materials with a scalar dielectric function.

    View details for DOI 10.1126/science.1216682

    View details for PubMedID 22223793

  • Temperature dependence of surface phonon polaritons from a quartz grating (vol 110, 043517, 2011) JOURNAL OF APPLIED PHYSICS Hafeli, A. K., Rephaeli, E., Fan, S., Cahill, D. G., Tiwald, T. E. 2012; 111 (1)

    View details for DOI 10.1063/1.3665444

    View details for Web of Science ID 000299127200132

  • Stacked Fano Resonance Photonic Crystal Nanomembrane High-Q Filters 25th IEEE Photonics Conference (IPC) Shuai, Y., Zhao, D., Tian, Z., Seo, J., Jacobson, R. B., Plant, D. V., Lagally, M. G., Fan, S., Ma, Z., Zhou, W. IEEE. 2012: 721–722
  • From electromagnetically induced transparency to superscattering with a single structure: A coupled-mode theory for doubly resonant structures Verslegers, L., Yu, Z., Ruan, Z., Catrysse, P. B., Fan, S., Adibi, A., Lin, S. Y., Scherer, A. SPIE-INT SOC OPTICAL ENGINEERING. 2012

    View details for DOI 10.1117/12.909576

    View details for Web of Science ID 000302582400010

  • Electro-optical silicon isolator Lira, H. R., Yu, Z., Fan, S., Lipson, M., IEEE IEEE. 2012
  • Resonance Fluorescence in a Waveguide Geometry Kocabas, S., Rephaeli, E., Fan, S., IEEE IEEE. 2012
  • GaAs thin film nanostructure arrays for III-V solar cell applications Conference on Photonic and Phononic Properties of Engineered Nanostructures II Liang, D., Kang, Y., Huo, Y., Wang, K. X., Gu, A., Tan, M., Yu, Z., Lia, S., Jia, J., Bao, X., Wang, S., Yao, Y., Fan, S., Cui, Y., Harris, J. SPIE-INT SOC OPTICAL ENGINEERING. 2012

    View details for DOI 10.1117/12.909743

    View details for Web of Science ID 000302582400036

  • Slow Light in Fiber Sensors Conference on Advances in Slow and Fast Light V Digonnet, M. J., Wen, H., Terrel, M. A., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2012

    View details for DOI 10.1117/12.915293

    View details for Web of Science ID 000305324800014

  • From Electromagnetically Induced Transparency to Superscattering with a Single Structure: A Coupled-Mode Theory for Doubly Resonant Structures Physical Review Letters Fan, S., H., Verslegers, L., Yu, Z., F., Ruan et al., Z., C. 2012; 108 (8)
  • Temporal coupled-mode theory for light scattering by an arbitrarily shaped object supporting a single resonance Physical Review A Ruan, Z., C., Fan, S., H. 2012; 85 (4)
  • Resonance fluorescence in a waveguide geometry Physical Review A Kocabas, S., E., Rephaeli, E., Fan, S., H. 2012; 85 (2)
  • Thermodynamic Upper Bound on Broadband Light Coupling with Photonic Structures Physical Review Letters Yu, Z., F., Raman, A., Fan, S., H. 2012; 109 (17)
  • Temperature dependence of surface phonon polaritons from a quartz grating (vol 110, 043517, 2011) Journal of Applied Physics Hafeli, A., K., Rephaeli, E., Fan et. al., S., H. 2012; 111 (1)

    View details for DOI 019902 10.1063/1.3665444

  • Photonic Aharonov-Bohm Effect Based on Dynamic Modulation Physical Review Letters Fang, K., J., Yu, Z., F., Fan, S., H. 2012; 108 (15)
  • Negative differential thermal conductance through vacuum Applied Physics Letters Zhu, L., Otey, C., R., Fan, S., H. 2012; 100 (4)

    View details for DOI 044104 10.1063/1.3679694

  • Comment on "Nonreciprocal Light Propagation in a Silicon Photonic Circuit Science Fan, S., H., Baets, R., Petrov et. al., A. 2012; 335 (6064): 38; author reply 38

    Abstract

    We show that the structure demonstrated by Feng et al. (Reports, 5 August 2011, p. 729) cannot enable optical isolation because it possesses a symmetric scattering matrix. Moreover, one cannot construct an optical isolator by incorporating this structure into any system as long as the system is linear and time-independent and is described by materials with a scalar dielectric function.

    View details for DOI 10.1126/science.1216682

  • Broadband light management using low-Q whispering gallery modes in spherical nanoshells Nature Communications Fan, S., H., Yao, Y., Yao, J., Narasimhan et. al., V., K. 2012; 3

    View details for DOI 664 10.1038/ncomms1664

  • Stimulated Emission from a Single Excited Atom in a Waveguide Physical Review Letters Rephaeli, E., Fan, S., H. 2012; 108 (14)
  • Enhancing the waveguide-resonator optical force with an all-optical on-chip analog of electromagnetically induced transparency Physical Review A Intaraprasonk, V., Fan, S., H. 2012; 86 (6)
  • Electrically Driven Nonreciprocity Induced by Interband Photonic Transition on a Silicon Chip Physical Review Letters Lira, H., Yu, Z., F., Fan et. al., S., H. 2012; 109 (3)
  • Rectification of evanescent heat transfer between dielectric-coated and uncoated silicon carbide plates Journal of Applied Physics Iizuka, H., Fan, S., H. 2012; 112 (2)

    View details for DOI 10.1063/1.4737465

  • Extraordinarily high spectral sensitivity in refractive index sensors using multiple optical modes Conference on Lasers and Electro-Optics (CLEO) Yu, Z., Fan, S. IEEE. 2012
  • Deep sub-wavelength beam propagation, beam manipulation and imaging with extreme anisotropic meta-materials Conference on Lasers and Electro-Optics (CLEO) Catrysse, P. B., Fan, S. IEEE. 2012
  • Photonic transitions can induce non-reciprocity and effective gauge field for photons 5th International Workshop on Theoretical and Computational Nano-Photonics (TaCoNa-Photonics) Fan, S., Fang, K., Yu, Z. AMER INST PHYSICS. 2012: 16–17

    View details for DOI 10.1063/1.4750080

    View details for Web of Science ID 000309602000005

  • Choice of the Perfectly Matched Layer boundary condition for iterative solvers of the frequency-domain Maxwell's equations Conference on Physics and Simulation of Optoelectronic Devices XX Shin, W., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2012

    View details for DOI 10.1117/12.906869

    View details for Web of Science ID 000302993700016

  • Improving fiber optic gyroscope performance using a laser and photonic-bandgap fiber 22nd International Conference on Optical Fiber Sensors (OFS) Lloyd, S., Fan, S., Digonnet, M. J. SPIE-INT SOC OPTICAL ENGINEERING. 2012

    View details for DOI 10.1117/12.2000380

    View details for Web of Science ID 000313011500009

  • Sensing With Slow Light in Fiber Bragg Gratings IEEE SENSORS JOURNAL Wen, H., Terrel, M., Fan, S., Digonnet, M. 2012; 12 (1): 156-163
  • Optical Transmission through Arbitrarily Located Subwavelength Apertures on Metal Films Conference on Lasers and Electro-Optics (CLEO) Tanemura, T., Wahl, P., Fan, S., Miller, D. A. IEEE. 2012
  • Numerically exact calculation of electromagnetic heat transfer between a dielectric sphere and plate PHYSICAL REVIEW B Otey, C., Fan, S. 2011; 84 (24)
  • Few-photon transport in a waveguide coupled to a pair of colocated two-level atoms PHYSICAL REVIEW A Rephaeli, E., Kocabas, S. E., Fan, S. 2011; 84 (6)
  • Two-photon transport in a waveguide coupled to a cavity in a two-level system PHYSICAL REVIEW A Shi, T., Fan, S., Sun, C. P. 2011; 84 (6)
  • Wireless energy transfer with the presence of metallic planes APPLIED PHYSICS LETTERS Yu, X., Sandhu, S., Beiker, S., Sassoon, R., Fan, S. 2011; 99 (21)

    View details for DOI 10.1063/1.3663576

    View details for Web of Science ID 000297471000055

  • Nanophotonic light-trapping theory for solar cells APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING Yu, Z., Raman, A., Fan, S. 2011; 105 (2): 329-339
  • Ultracompact nonreciprocal optical isolator based on guided resonance in a magneto-optical photonic crystal slab OPTICS LETTERS Fang, K., Yu, Z., Liu, V., Fan, S. 2011; 36 (21): 4254-4256

    Abstract

    We design an ultracompact optical isolator with normal incident geometry that operates with a bandwidth that is substantial for a device of this size. For operation in a telecommunication wavelength of 1.55 μm, the thickness of the device is less than 1 μm and the device supports an operating bandwidth of 400 GHz over which the minimum contrast ratio exceeds 25 dB. Our design utilizes guided resonance in a photonic crystal slab to enhance magneto-optical effects, and exploits interference effects among multiple resonances to create desired transmission spectral line shapes.

    View details for Web of Science ID 000296734700045

    View details for PubMedID 22048382

  • Dielectric nanostructures for broadband light trapping in organic solar cells OPTICS EXPRESS Raman, A., Yu, Z., Fan, S. 2011; 19 (20): 19015-19026

    Abstract

    Organic bulk heterojunction solar cells are a promising candidate for low-cost next-generation photovoltaic systems. However, carrier extraction limitations necessitate thin active layers that sacrifice absorption for internal quantum efficiency or vice versa. Motivated by recent theoretical developments, we show that dielectric wavelength-scale grating structures can produce significant absorption resonances in a realistic organic cell architecture. We numerically demonstrate that 1D, 2D and multi-level ITO-air gratings lying on top of the organic solar cell stack produce a 8-15% increase in photocurrent for a model organic solar cell where PCDTBT:PC(71)BM is the organic semiconductor. Specific to this approach, the active layer itself remains untouched yet receives the benefit of light trapping by nanostructuring the top surface below which it lies. The techniques developed here are broadly applicable to organic semiconductors in general, and enable partial decoupling between active layer thickness and photocurrent generation.

    View details for Web of Science ID 000295373800026

    View details for PubMedID 21996842

  • OPTICAL ISOLATION A non-magnetic approach NATURE PHOTONICS Yu, Z., Fan, S. 2011; 5 (9): 517-519
  • Temperature dependence of surface phonon polaritons from a quartz grating JOURNAL OF APPLIED PHYSICS Hafeli, A. K., Rephaeli, E., Fan, S., Cahill, D. G., Tiwald, T. E. 2011; 110 (4)

    View details for DOI 10.1063/1.3624603

    View details for Web of Science ID 000294484300037

  • Microscopic theory of photonic one-way edge mode PHYSICAL REVIEW B Fang, K., Yu, Z., Fan, S. 2011; 84 (7)
  • Complete All-Optical Silica Fiber Isolator via Stimulated Brillouin Scattering JOURNAL OF LIGHTWAVE TECHNOLOGY Huang, X., Fan, S. 2011; 29 (15): 2267-2275
  • Efficient computation of equifrequency surfaces and density of states in photonic crystals using Dirichlet-to-Neumann maps JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS Liu, V., Fan, S. 2011; 28 (8): 1837-1843
  • Nonvolatile bistable all-optical switch from mechanical buckling APPLIED PHYSICS LETTERS Intaraprasonk, V., Fan, S. 2011; 98 (24)

    View details for DOI 10.1063/1.3600335

    View details for Web of Science ID 000291803600004

  • Transverse Electromagnetic Modes in Aperture Waveguides Containing a Metamaterial with Extreme Anisotropy PHYSICAL REVIEW LETTERS Catrysse, P. B., Fan, S. 2011; 106 (22)

    Abstract

    We use metamaterials with extreme anisotropy to solve the fundamental problem of light transport in deep subwavelength apertures. By filling a simply connected aperture with an anisotropic medium, we decouple the cutoff frequency and the group velocity of modes inside apertures. In the limit of extreme anisotropy, all modes become purely transverse electromagnetic modes, free from geometrical dispersion, propagate with a velocity controlled by the transverse permittivity and permeability, and have zero cutoff frequency. We analyze physically realizable cases for a circular aperture and show a metamaterial design using existing materials.

    View details for DOI 10.1103/PhysRevLett.106.223902

    View details for Web of Science ID 000291199000006

    View details for PubMedID 21702600

  • Perturbation theory for plasmonic modulation and sensing PHYSICAL REVIEW B Raman, A., Fan, S. 2011; 83 (20)
  • Extraordinarily high spectral sensitivity in refractive index sensors using multiple optical modes OPTICS EXPRESS Yu, Z., Fan, S. 2011; 19 (11): 10029-10040

    Abstract

    The extraordinary spectral sensitivity of surface plasmon resonance (SPR) sensors is commonly attributed to the modal overlap or unique dispersion of surface plasmons. In contrast to this belief, we show that such high sensitivity is due to the multi-mode nature of the sensing scheme. This concept of multi-mode sensing can be applied to dielectric systems as well in order to achieve similar extraordinary spectral sensitivity. We also show that there is a fundamental constraint between the spectral sensitivity and quality factor in such multi-mode sensing approach.

    View details for Web of Science ID 000290852800001

    View details for PubMedID 21643261

  • Image transfer with subwavelength resolution to metal-dielectric interface JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS Intaraprasonk, V., Yu, Z., Fan, S. 2011; 28 (5): 1335-1338
  • Experimental demonstration of two methods for controlling the group delay in a system with photonic-crystal resonators coupled to a waveguide OPTICS LETTERS Huo, Y., Sandhu, S., Pan, J., Stuhrmann, N., Povinelli, M. L., Kahn, J. M., Harris, J. S., Fejer, M. M., Fan, S. 2011; 36 (8): 1482-1484

    Abstract

    We measure the group delay in an on-chip photonic-crystal device with two resonators side coupled to a waveguide. We demonstrate that such a group delay can be controlled by tuning either the propagation phase of the waveguide or the frequency of the resonators.

    View details for Web of Science ID 000290034500059

    View details for PubMedID 21499397

  • Design methodology for compact photonic-crystal-based wavelength division multiplexers OPTICS LETTERS Liu, V., Jiao, Y., Miller, D. A., Fan, S. 2011; 36 (4): 591-593

    Abstract

    We present an extremely compact wavelength division multiplexer design, as well as a general framework for designing and optimizing frequency selective devices embedded in photonic crystals satisfying arbitrary design constraints. Our method is based on the Dirichlet-to-Neumman simulation method and uses low rank updates to the system to efficiently scan through many device designs.

    View details for Web of Science ID 000287395500055

    View details for PubMedID 21326466

  • Design of subwavelength superscattering nanospheres APPLIED PHYSICS LETTERS Ruan, Z., Fan, S. 2011; 98 (4)

    View details for DOI 10.1063/1.3536475

    View details for Web of Science ID 000286676600041

  • Low Reflectivity and High Flexibility of Tin-Doped Indium Oxide Nanofiber Transparent Electrodes JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Wu, H., Hu, L., Carney, T., Ruan, Z., Kong, D., Yu, Z., Yao, Y., Cha, J. J., Zhu, J., Fan, S., Cui, Y. 2011; 133 (1): 27-29

    Abstract

    Tin-doped indium oxide (ITO) has found widespread use in solar cells, displays, and touch screens as a transparent electrode; however, two major problems with ITO remain: high reflectivity (up to 10%) and insufficient flexibility. Together, these problems severely limit the applications of ITO films for future optoelectronic devices. In this communication, we report the fabrication of ITO nanofiber network transparent electrodes. The nanofiber networks show optical reflectivity as low as 5% and high flexibility; the nanofiber networks can be bent to a radius of 2 mm with negligible changes in the sheet resistance.

    View details for DOI 10.1021/ja109228e

    View details for Web of Science ID 000286351100009

    View details for PubMedID 21142042

  • Angular constraint on light-trapping absorption enhancement in solar cells APPLIED PHYSICS LETTERS Yu, Z., Fan, S. 2011; 98 (1)

    View details for DOI 10.1063/1.3532099

    View details for Web of Science ID 000286009800007

  • Integrated photonic structures for parallel fluorescence and refractive index biosensing Conference on Photonic Microdevices/Microstructures for Sensing III Lee, M. M., O'Sullivan, T. D., Cerruto, A., Liu, V., Zhang, J., Levi, O., Lee, H., Brueck, S. R., Fan, S., Harris, J. S. SPIE-INT SOC OPTICAL ENGINEERING. 2011

    View details for DOI 10.1117/12.884228

    View details for Web of Science ID 000294154700005

  • Near shot-noise-limited performance of an open-loop laser-driven interferometric fiber optic gyroscope 21st International Conference on Optical Fiber Sensors Lloyd, S. W., Digonnet, M. J., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2011

    View details for DOI 10.1117/12.899550

    View details for Web of Science ID 000293567800362

  • Wireless energy transfer with the presence of metallic planes Applied Physics Letters Fan, S., H., Yu, X., F., Sandhu, S., Beiker et. al., S. 2011; 99 (21)

    View details for DOI 214102 10.1063/1.3663576

  • Nanophotonic light-trapping theory for solar cells Applied Physics a-Materials Science & Processing Yu, Z., F., Raman, A., Fan, S., H. 2011; 2: 105
  • Angular constraint on light-trapping absorption enhancement in solar cells Applied Physics Letters Yu, Z., F., Fan, S., H. 2011; 98 (1)

    View details for DOI 011106 10.1063/1.3532099

  • Two-photon transport in a waveguide coupled to a cavity in a two-level system Physical Review A Shi, T., Fan, S., H., Sun, C., P. 2011; 84 (6)
  • Temperature dependence of surface phonon polaritons from a quartz grating ournal of Applied Physics Hafeli, A., K., Rephaeli, E., Fan et. al., S., H. 2011; 110 (4)

    View details for DOI 043517 10.1063/1.3624603

  • Perturbation theory for plasmonic modulation and sensing Physical Review B Raman, A., Fan, S., H. 2011; 83 (20)
  • Few-photon transport in a waveguide coupled to a pair of colocated two-level atoms Physical Review A Rephaeli, E., Kocabas, S., E., Fan, S., H. 2011; 84 (6)
  • Nonvolatile bistable all-optical switch from mechanical buckling Applied Physics Letters Intaraprasonk, V., Fan, S., H. 2011; 98 (24)

    View details for DOI 241104 10.1063/1.3600335

  • Transverse Electromagnetic Modes in Aperture Waveguides Containing a Metamaterial with Extreme Anisotropy Physical Review Letters Catrysse, P., B., Fan, S., H. 2011; 106 (22)
  • Numerically exact calculation of electromagnetic heat transfer between a dielectric sphere and plate Physical Review B Otey, C., Fan, S., H. 2011; 84 (24)
  • Microscopic theory of photonic one-way edge mode Physical Review B Fang, K., J., Yu, Z., F., Fan, S., H. 2011; 84 (7)
  • Design of subwavelength superscattering nanospheres Applied Physics Letters Ruan, Z., C., Fan, S., H. 2011; 98 (4)

    View details for DOI 043101 10.1063/1.3536475

  • Transverse electro-magnetic modes in apertures filled with an extreme anisotropic meta-material Conference on Lasers and Electro-Optics (CLEO) Catrysse, P. B., Fan, S. IEEE. 2011
  • Temporal Coupled-Mode Theory for Resonant Apertures Conference on Lasers and Electro-Optics (CLEO) Verslegers, L., Yu, Z., Catrysse, P. B., Ruan, Z., Fan, S. IEEE. 2011
  • Dielectric nanostructures for broadband light trapping in organic solar cells Conference on Lasers and Electro-Optics (CLEO) Raman, A., Yu, Z., Fan, S. IEEE. 2011
  • Tactical-grade interferometric fiber optic gyroscope driven with a narrow-linewidth laser 21st International Conference on Optical Fiber Sensors Lloyd, S. W., Digonnet, M. J., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2011

    View details for DOI 10.1117/12.886025

    View details for Web of Science ID 000293567800067

  • Slow Light in Fiber Bragg Gratings Conference on Advances in Slow and Fast Light IV Wen, H., Skolianos, G., Fan, S., Digonnet, M. SPIE-INT SOC OPTICAL ENGINEERING. 2011

    View details for DOI 10.1117/12.880795

    View details for Web of Science ID 000293700300010

  • Tight Binding Model Study of Photonic One-Way Edge Mode Conference on Lasers and Electro-Optics (CLEO) Fang, K., Yu, Z., Fan, S. IEEE. 2011
  • Input-output formalism for few-photon transport in one-dimensional nanophotonic waveguides coupled to a qubit PHYSICAL REVIEW A Fan, S., Kocabas, S. E., Shen, J. 2010; 82 (6)
  • Elements for Plasmonic Nanocircuits with Three-Dimensional Slot Waveguides ADVANCED MATERIALS Cai, W., Shin, W., Fan, S., Brongersma, M. L. 2010; 22 (45): 5120-?

    View details for DOI 10.1002/adma.201001440

    View details for Web of Science ID 000285396400010

    View details for PubMedID 20859937

  • Nanostructured photon management for high performance solar cells MATERIALS SCIENCE & ENGINEERING R-REPORTS Zhu, J., Yu, Z., Fan, S., Cui, Y. 2010; 70 (3-6): 330-340
  • Sensitivity enhancement in photonic crystal slab biosensors OPTICS EXPRESS El Beheiry, M., Liu, V., Fan, S., Levi, O. 2010; 18 (22): 22702-22714

    Abstract

    Refractive index sensitivity of guided resonances in photonic crystal slabs is analyzed. We show that modal properties of guided resonances strongly affect spectral sensitivity and quality factors, resulting in substantial enhancement of refractive index sensitivity. A three-fold spectral sensitivity enhancement is demonstrated for suspended slab designs, in contrast to designs with a slab resting over a substrate. Spectral sensitivity values are additionally shown to be unaffected by quality factor reductions, which are common to fabricated photonic crystal nano-structures. Finally, we determine that proper selection of photonic crystal slab design parameters permits biosensing of a wide range of analytes, including proteins, antigens, and cells. These photonic crystals are compatible with large-area biosensor designs, permitting direct access to externally incident optical beams in a microfluidic device.

    View details for Web of Science ID 000283560400009

    View details for PubMedID 21164609

  • Fundamental limit of nanophotonic light trapping in solar cells PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Yu, Z., Raman, A., Fan, S. 2010; 107 (41): 17491-17496

    Abstract

    Establishing the fundamental limit of nanophotonic light-trapping schemes is of paramount importance and is becoming increasingly urgent for current solar cell research. The standard theory of light trapping demonstrated that absorption enhancement in a medium cannot exceed a factor of 4n(2)/sin(2)θ, where n is the refractive index of the active layer, and θ is the angle of the emission cone in the medium surrounding the cell. This theory, however, is not applicable in the nanophotonic regime. Here we develop a statistical temporal coupled-mode theory of light trapping based on a rigorous electromagnetic approach. Our theory reveals that the conventional limit can be substantially surpassed when optical modes exhibit deep-subwavelength-scale field confinement, opening new avenues for highly efficient next-generation solar cells.

    View details for DOI 10.1073/pnas.1008296107

    View details for Web of Science ID 000282809700012

    View details for PubMedID 20876131

    View details for PubMedCentralID PMC2955111

  • The MicroArray Quality Control (MAQC)-II study of common practices for the development and validation of microarray-based predictive models PHARMACOGENOMICS JOURNAL Shi, L., Campbell, G., Jones, W. D., Campagne, F., Wen, Z., Walker, S. J., Su, Z., Chu, T., Goodsaid, F. M., Pusztai, L., Shaughnessy, J. D., Oberthuer, A., Thomas, R. S., Paules, R. S., Fielden, M., Barlogie, B., Chen, W., Du, P., Fischer, M., Furlanello, C., Gallas, B. D., Ge, X., Megherbi, D. B., Symmans, W. F., Wang, M. D., Zhang, J., Bitter, H., Brors, B., Bushel, P. R., Bylesjo, M., Chen, M., Cheng, J., Cheng, J., Chou, J., Davison, T. S., Delorenzi, M., Deng, Y., Devanarayan, V., Dix, D. J., Dopazo, J., Dorff, K. C., Elloumi, F., Fan, J., Fan, S., Fan, X., Fang, H., Gonzaludo, N., Hess, K. R., Hong, H., Huan, J., Irizarry, R. A., Judson, R., Juraeva, D., Lababidi, S., Lambert, C. G., Li, L., Li, Y., Li, Z., Lin, S. M., Liu, G., Lobenhofer, E. K., Luo, J., Luo, W., McCall, M. N., Nikolsky, Y., Pennello, G. A., Perkins, R. G., Philip, R., Popovici, V., Price, N. D., Qian, F., Scherer, A., Shi, T., Shi, W., Sung, J., Thierry-Mieg, D., Thierry-Mieg, J., Thodima, V., Trygg, J., Vishnuvajjala, L., Wang, S. J., Wu, J., Wu, Y., Xie, Q., Yousef, W. A., Zhang, L., Zhang, X., Zhong, S., Zhou, Y., Zhu, S., Arasappan, D., Bao, W., Lucas, A. B., Berthold, F., Brennan, R. J., Buness, A., Catalano, J. G., Chang, C., Chen, R., Cheng, Y., Cui, J., Czika, W., Demichelis, F., Deng, X., Dosymbekov, D., Eils, R., Feng, Y., Fostel, J., Fulmer-Smentek, S., Fuscoe, J. C., Gatto, L., Ge, W., Goldstein, D. R., Guo, L., Halbert, D. N., Han, J., Harris, S. C., Hatzis, C., Herman, D., Huang, J., Jensen, R. V., Jiang, R., Johnson, C. D., Jurman, G., Kahlert, Y., Khuder, S. A., Kohl, M., Li, J., Li, L., Li, M., Li, Q., Li, S., Li, Z., Liu, J., Liu, Y., Liu, Z., Meng, L., Madera, M., Martinez-Murillo, F., Medina, I., Meehan, J., Miclaus, K., Moffitt, R. A., Montaner, D., Mukherjee, P., Mulligan, G. J., Neville, P., Nikolskaya, T., Ning, B., Page, G. P., Parker, J., Parry, R. M., Peng, X., Peterson, R. L., Phan, J. H., Quanz, B., Ren, Y., Riccadonna, S., Roter, A. H., Samuelson, F. W., Schumacher, M. M., Shambaugh, J. D., Shi, Q., Shippy, R., Si, S., Smalter, A., Sotiriou, C., Soukup, M., Staedtler, F., Steiner, G., Stokes, T. H., Sun, Q., Tan, P., Tang, R., Tezak, Z., Thorn, B., Tsyganova, M., Turpaz, Y., Vega, S. C., Visintainer, R., von Frese, J., Wang, C., Wang, E., Wang, J., Wang, W., Westermann, F., Willey, J. C., Woods, M., Wu, S., Xiao, N., Xu, J., Xu, L., Yang, L., Zeng, X., Zhang, J., Zhang, L., Zhang, M., Zhao, C., Puri, R. K., Scherf, U., Tong, W., Wolfinger, R. D. 2010: S5-S16

    View details for DOI 10.1038/nbt.1665

    View details for Web of Science ID 000285268700003

  • Temporal coupled-mode theory for resonant apertures JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS Verslegers, L., Yu, Z., Catrysse, P. B., Fan, S. 2010; 27 (10): 1947-1956
  • Exponential suppression of thermal conductance using coherent transport and heterostructures PHYSICAL REVIEW B Lau, W. T., Shen, J., Fan, S. 2010; 82 (11)
  • Fundamental limit of light trapping in grating structures OPTICS EXPRESS Yu, Z., Raman, A., Fan, S. 2010; 18 (19): A366-A380

    Abstract

    We use a rigorous electromagnetic approach to analyze the fundamental limit of light-trapping enhancement in grating structures. This limit can exceed the bulk limit of 4n², but has significant angular dependency. We explicitly show that 2D gratings provide more enhancement than 1D gratings. We also show the effects of the grating profile's symmetry on the absorption enhancement limit. Numerical simulations are applied to support the theory. Our findings provide general guidance for the design of grating structures for light-trapping solar cells.

    View details for Web of Science ID 000285263500004

    View details for PubMedID 21165067

  • Full inversion of a two-level atom with a single-photon pulse in one-dimensional geometries PHYSICAL REVIEW A Rephaeli, E., Shen, J., Fan, S. 2010; 82 (3)
  • Tuning the coherent interaction in an on-chip photonic-crystal waveguide-resonator system APPLIED PHYSICS LETTERS Pan, J., Huo, Y., Sandhu, S., Stuhrmann, N., Povinelli, M. L., Harris, J. S., Fejer, M. M., Fan, S. 2010; 97 (10)

    View details for DOI 10.1063/1.3486686

    View details for Web of Science ID 000282478800002

  • Quantum critical coupling conditions for zero single-photon transmission through a coupled atom-resonator-waveguide system PHYSICAL REVIEW A Shen, J., Fan, S. 2010; 82 (2)
  • The MicroArray Quality Control (MAQC)-IIII study of common practices for the development and validation of microarray-based predictive models NATURE BIOTECHNOLOGY Shi, L., Campbell, G., Jones, W. D., Campagne, F., Wen, Z., Walker, S. J., Su, Z., Chu, T., Goodsaid, F. M., Pusztai, L., Shaughnessy, J. D., Oberthuer, A., Thomas, R. S., Paules, R. S., Fielden, M., Barlogie, B., Chen, W., Du, P., Fischer, M., Furlanello, C., Gallas, B. D., Ge, X., Megherbi, D. B., Symmans, W. F., Wang, M. D., Zhang, J., Bitter, H., Brors, B., Bushel, P. R., Bylesjo, M., Chen, M., Cheng, J., Cheng, J., Chou, J., Davison, T. S., Delorenzi, M., Deng, Y., Devanarayan, V., Dix, D. J., Dopazo, J., Dorff, K. C., Elloumi, F., Fan, J., Fan, S., Fan, X., Fang, H., Gonzaludo, N., Hess, K. R., Hong, H., Huan, J., Irizarry, R. A., Judson, R., Juraeva, D., Lababidi, S., Lambert, C. G., Li, L., Li, Y., Li, Z., Lin, S. M., Liu, G., Lobenhofer, E. K., Luo, J., Luo, W., McCall, M. N., Nikolsky, Y., Pennello, G. A., Perkins, R. G., Philip, R., Popovici, V., Price, N. D., Qian, F., Scherer, A., Shi, T., Shi, W., Sung, J., Thierry-Mieg, D., Thierry-Mieg, J., Thodima, V., Trygg, J., Vishnuvajjala, L., Wang, S. J., Wu, J., Wu, Y., Xie, Q., Yousef, W. A., Zhang, L., Zhang, X., Zhong, S., Zhou, Y., Zhu, S., Arasappan, D., Bao, W., Lucas, A. B., Berthold, F., Brennan, R. J., Buness, A., Catalano, J. G., Chang, C., Chen, R., Cheng, Y., Cui, J., Czika, W., Demichelis, F., Deng, X., Dosymbekov, D., Eils, R., Feng, Y., Fostel, J., Fulmer-Smentek, S., Fuscoe, J. C., Gatto, L., Ge, W., Goldstein, D. R., Guo, L., Halbert, D. N., Han, J., Harris, S. C., Hatzis, C., Herman, D., Huang, J., Jensen, R. V., Jiang, R., Johnson, C. D., Jurman, G., Kahlert, Y., Khuder, S. A., Kohl, M., Li, J., Li, L., Li, M., Li, Q., Li, S., Li, Z., Liu, J., Liu, Y., Liu, Z., Meng, L., Madera, M., Martinez-Murillo, F., Medina, I., Meehan, J., Miclaus, K., Moffitt, R. A., Montaner, D., Mukherjee, P., Mulligan, G. J., Neville, P., Nikolskaya, T., Ning, B., Page, G. P., Parker, J., Parry, R. M., Peng, X., Peterson, R. L., Phan, J. H., Quanz, B., Ren, Y., Riccadonna, S., Roter, A. H., Samuelson, F. W., Schumacher, M. M., Shambaugh, J. D., Shi, Q., Shippy, R., Si, S., Smalter, A., Sotiriou, C., Soukup, M., Staedtler, F., Steiner, G., Stokes, T. H., Sun, Q., Tan, P., Tang, R., Tezak, Z., Thorn, B., Tsyganova, M., Turpaz, Y., Vega, S. C., Visintainer, R., von Frese, J., Wang, C., Wang, E., Wang, J., Wang, W., Westermann, F., Willey, J. C., Woods, M., Wu, S., Xiao, N., Xu, J., Xu, L., Yang, L., Zeng, X., Zhang, J., Zhang, L., Zhang, M., Zhao, C., Puri, R. K., Scherf, U., Tong, W., Wolfinger, R. D. 2010; 28 (8): 827-U109

    Abstract

    Gene expression data from microarrays are being applied to predict preclinical and clinical endpoints, but the reliability of these predictions has not been established. In the MAQC-II project, 36 independent teams analyzed six microarray data sets to generate predictive models for classifying a sample with respect to one of 13 endpoints indicative of lung or liver toxicity in rodents, or of breast cancer, multiple myeloma or neuroblastoma in humans. In total, >30,000 models were built using many combinations of analytical methods. The teams generated predictive models without knowing the biological meaning of some of the endpoints and, to mimic clinical reality, tested the models on data that had not been used for training. We found that model performance depended largely on the endpoint and team proficiency and that different approaches generated models of similar performance. The conclusions and recommendations from MAQC-II should be useful for regulatory agencies, study committees and independent investigators that evaluate methods for global gene expression analysis.

    View details for DOI 10.1038/nbt.1665

    View details for Web of Science ID 000280757500023

    View details for PubMedID 20676074

    View details for PubMedCentralID PMC3315840

  • Nanopatterned Metallic Films for Use As Transparent Conductive Electrodes in Optoelectronic Devices NANO LETTERS Catrysse, P. B., Fan, S. 2010; 10 (8): 2944-2949

    Abstract

    We investigate the use of nanopatterned metallic films as transparent conductive electrodes in optoelectronic devices. We find that the physics of nanopatterned electrodes, which are often optically thin metallic films, differs from that of optically thick metallic films. We analyze the optical properties when performing a geometrical transformation that maintains the electrical properties. For one-dimensional patterns of metallic wires, the analysis favors tall and narrow wires. Our design principles remain valid for oblique incidence and readily carry over to two-dimensional patterns.

    View details for DOI 10.1021/nl1011239

    View details for Web of Science ID 000280728900035

    View details for PubMedID 20698607

  • Superscattering of Light from Subwavelength Nanostructures PHYSICAL REVIEW LETTERS Ruan, Z., Fan, S. 2010; 105 (1)

    Abstract

    We provide a theoretical discussion of the scattering cross section of individual subwavelength structures. We show that, in principle, an arbitrarily large total cross section can be achieved, provided that one maximizes contributions from a sufficiently large number of channels. As a numerical demonstration, we present a subwavelength nanorod with a plasmonic-dielectric-plasmonic layer structure, where the scattering cross section far exceeds the single-channel limit, even in the presence of loss.

    View details for DOI 10.1103/PhysRevLett.105.013901

    View details for Web of Science ID 000279273600001

    View details for PubMedID 20867445

  • Optimization of the splice loss between photonic-bandgap fibers and conventional single-mode fibers OPTICS LETTERS Aghaie, K. Z., Digonnet, M. J., Fan, S. 2010; 35 (12): 1938-1940

    Abstract

    To understand the loss limitations of a splice between a hollow-core fiber and a conventional fiber, we use a numerical model to calculate the expected coupling loss between the NKT Photonics' HC-1550-02 fiber and a single-mode fiber (SMF) of arbitrary step-index profile. When the SMF parameters are optimized, the splice loss is predicted to be as low as approximately 0.6 dB. This minimum is believed to be largely due to mode-shape mismatch. These predictions are confirmed experimentally by optimizing the splice loss between this photonic-bandgap fiber and five SMFs with different mode-field diameters (MFDs) and V numbers. With the SMF-28 fiber, the measured loss is 1.3 dB, in excellent agreement with theory. Using a SMF with parameters close to the optimum values (MFD=7.2 microm and V=2.16), this loss was reduced to a new record value of 0.79 dB.

    View details for Web of Science ID 000279435800004

    View details for PubMedID 20548345

  • Enhancing optical switching with coherent control APPLIED PHYSICS LETTERS Sandhu, S., Povinelli, M. L., Fan, S. 2010; 96 (23)

    View details for DOI 10.1063/1.3449572

    View details for Web of Science ID 000278695900008

  • Nanodome Solar Cells with Efficient Light Management and Self-Cleaning NANO LETTERS Zhu, J., Hsu, C., Yu, Z., Fan, S., Cui, Y. 2010; 10 (6): 1979-1984

    Abstract

    Here for the first time, we demonstrate novel nanodome solar cells, which have periodic nanoscale modulation for all layers from the bottom substrate, through the active absorber to the top transparent contact. These devices combine many nanophotonic effects to both efficiently reduce reflection and enhance absorption over a broad spectral range. Nanodome solar cells with only a 280 nm thick hydrogenated amorphous silicon (a-Si:H) layer can absorb 94% of the light with wavelengths of 400-800 nm, significantly higher than the 65% absorption of flat film devices. Because of the nearly complete absorption, a very large short-circuit current of 17.5 mA/cm(2) is achieved in our nanodome devices. Excitingly, the light management effects remain efficient over a wide range of incident angles, favorable for real environments with significant diffuse sunlight. We demonstrate nanodome devices with a power efficiency of 5.9%, which is 25% higher than the flat film control. The nanodome structure is not in principle limited to any specific material system and its fabrication is compatible with most solar manufacturing; hence it opens up exciting opportunities for a variety of photovoltaic devices to further improve performance, reduce materials usage, and relieve elemental abundance limitations. Lastly, our nanodome devices when modified with hydrophobic molecules present a nearly superhydrophobic surface and thus enable self-cleaning solar cells.

    View details for DOI 10.1021/nl9034237

    View details for Web of Science ID 000278449200002

    View details for PubMedID 19891462

  • Birefringence Analysis of Photonic-Bandgap Fibers Using the Hexagonal Yee's Cell IEEE JOURNAL OF QUANTUM ELECTRONICS Aghaie, K. Z., Fan, S., Digonnet, M. J. 2010; 46 (6): 920-930
  • Combining radiationless interference with evanescent field amplification OPTICS LETTERS Intaraprasonk, V., Yu, Z., Fan, S. 2010; 35 (10): 1659-1661

    Abstract

    The conventional approach for radiationless interference exploits the interference of evanescent components for the purpose of deep-subwavelength focusing and image formation. As a result, deep subwavelength feature size is achieved at the price of severe exponential decay of the field strength. We propose to overcome the limitation of the conventional approach by combining radiationless interference with evanescent field amplification as provided by the surface polaritons at the interface between positive- and negative-dielectric materials. Our approach removes the exponential decay and, moreover, allows a much wider range of wave vectors, including both propagating and evanescent field components, to participate in the image-formation process.

    View details for Web of Science ID 000277773400056

    View details for PubMedID 20479841

  • Temporal Coupled-Mode Theory for Fano Resonance in Light Scattering by a Single Obstacle JOURNAL OF PHYSICAL CHEMISTRY C Ruan, Z., Fan, S. 2010; 114 (16): 7324-7329

    View details for DOI 10.1021/jp9089722

    View details for Web of Science ID 000276889300018

  • Thermal Rectification through Vacuum PHYSICAL REVIEW LETTERS Otey, C. R., Lau, W. T., Fan, S. 2010; 104 (15)

    Abstract

    We propose a mechanism for photon mediated thermal rectification through vacuum relying only on the temperature dependence of electromagnetic resonances. We also propose an example implementation consisting of two polytypes of silicon carbide, which exploits the interaction of temperature dependent surface phonon polaritons to achieve significant rectification.

    View details for DOI 10.1103/PhysRevLett.104.154301

    View details for Web of Science ID 000277001700021

    View details for PubMedID 20481993

  • Enhancement of optical absorption in thin-film organic solar cells through the excitation of plasmonic modes in metallic gratings APPLIED PHYSICS LETTERS Min, C., Li, J., Veronis, G., Lee, J., Fan, S., Peumans, P. 2010; 96 (13)

    View details for DOI 10.1063/1.3377791

    View details for Web of Science ID 000276275300059

  • Phase front design with metallic pillar arrays OPTICS LETTERS Verslegers, L., Catrysse, P. B., Yu, Z., Shin, W., Ruan, Z., Fan, S. 2010; 35 (6): 844-846

    Abstract

    We demonstrate numerically, using a three-dimensional finite-difference frequency-domain method, the ability to design a phase front using an array of metallic pillars. We show that in such structures, the local phase delay upon transmission can be tuned by local geometry. We apply this knowledge to demonstrate a metallic microlens. The presented design principles apply to a wider range of wavelength-size integrated photonic components.

    View details for Web of Science ID 000275827000017

    View details for PubMedID 20237618

  • Transmission Through a Scalar Wave Three-Dimensional Electromagnetic Metamaterial and the Implication for Polarization Control JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY Shin, J., Shen, J., Fan, S. 2010; 10 (3): 1737-1740

    Abstract

    An interweaving-conductor metamaterial (ICM) is a metamaterial composed of multiple, interlocking, conducting networks. It exhibits unusual optical properties in the low-frequency linear-dispersion regime. In particular, two-network ICM supports only one, non-dispersive mode in the low frequency range, and is best described as an effective medium supporting a scalar wave in full three dimensions. We explore the light transmission properties of such a metamaterial, and the implications of a scalar wave medium for polarization control. Polarizers and polarization rotators with subwavelength sizes are numerically demonstrated.

    View details for DOI 10.1166/jnn.2010.2036

    View details for Web of Science ID 000273984800036

    View details for PubMedID 20355567

  • Multiplexed Five-Color Molecular Imaging of Cancer Cells and Tumor Tissues with Carbon Nanotube Raman Tags in the Near-Infrared NANO RESEARCH Liu, Z., Tabakman, S., Sherlock, S., Li, X., Chen, Z., Jiang, K., Fan, S., Dai, H. 2010; 3 (3): 222-233

    Abstract

    Single-walled carbon nanotubes (SWNTs) with five different C13/C12 isotope compositions and well-separated Raman peaks have been synthesized and conjugated to five targeting ligands in order to impart molecular specificity. Multiplexed Raman imaging of live cells has been carried out by highly specific staining of cells with a five-color mixture of SWNTs. Ex vivo multiplexed Raman imaging of tumor samples uncovers a surprising up-regulation of epidermal growth factor receptor (EGFR) on LS174T colon cancer cells from cell culture to in vivo tumor growth. This is the first time five-color multiplexed molecular imaging has been performed in the near-infrared (NIR) region under a single laser excitation. Near zero interfering background of imaging is achieved due to the sharp Raman peaks unique to nanotubes over the low, smooth autofluorescence background of biological species.

    View details for DOI 10.1007/s12274-010-1025-1

    View details for Web of Science ID 000275754900008

    View details for PubMedCentralID PMC3062899

  • Mapping local optical densities of states in silicon photonic structures with nanoscale electron spectroscopy PHYSICAL REVIEW B Cha, J. J., Yu, Z., Smith, E., Couillard, M., Fan, S., Muller, D. A. 2010; 81 (11)
  • Integrated Nonmagnetic Optical Isolators Based on Photonic Transitions IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS Yu, Z., Fan, S. 2010; 16 (2): 459-466
  • Photonic Band Structure of Dispersive Metamaterials Formulated as a Hermitian Eigenvalue Problem PHYSICAL REVIEW LETTERS Raman, A., Fan, S. 2010; 104 (8)

    Abstract

    We formulate the photonic band structure calculation of any lossless dispersive photonic crystal and optical metamaterial as a Hermitian eigenvalue problem. We further show that the eigenmodes of such lossless systems provide an orthonormal basis, which can be used to rigorously describe the behavior of lossy dispersive systems in general.

    View details for DOI 10.1103/PhysRevLett.104.087401

    View details for Web of Science ID 000275060000043

    View details for PubMedID 20366963

  • Semiconductor Nanowire Optical Antenna Solar Absorbers NANO LETTERS Cao, L., Fan, P., Vasudev, A. P., White, J. S., Yu, Z., Cai, W., Schuller, J. A., Fan, S., Brongersma, M. L. 2010; 10 (2): 439-445

    Abstract

    Photovoltaic (PV) cells can serve as a virtually unlimited clean source of energy by converting sunlight into electrical power. Their importance is reflected in the tireless efforts that have been devoted to improving the electrical and structural properties of PV materials. More recently, photon management (PM) has emerged as a powerful additional means to boost energy conversion efficiencies. Here, we demonstrate an entirely new PM strategy that capitalizes on strong broad band optical antenna effects in one-dimensional semiconductor nanostructures to dramatically enhance absorption of sunlight. We show that the absorption of sunlight in Si nanowires (Si NWs) can be significantly enhanced over the bulk. The NW's optical properties also naturally give rise to an improved angular response. We propose that by patterning the silicon layer in a thin film PV cell into an array of NWs, one can boost the absorption for solar radiation by 25% while utilizing less than half of the semiconductor material (250% increase in the light absorption per unit volume of material). These results significantly advance our understanding of the way sunlight is absorbed by one-dimensional semiconductor nanostructures and provide a clear, intuitive guidance for the design of efficient NW solar cells. The presented approach is universal to any semiconductor and a wide range of nanostructures; as such, it provides a new PV platform technology.

    View details for DOI 10.1021/nl9036627

    View details for Web of Science ID 000274338800013

    View details for PubMedID 20078065

  • NANOPHOTONICS Magnet-controlled plasmons NATURE PHOTONICS Fan, S. 2010; 4 (2): 76-77
  • Measurement of reduced backscattering noise in laser-driven fiber optic gyroscopes OPTICS LETTERS Lloyd, S. W., Dangui, V., Digonnet, M. J., Fan, S., Kino, G. S. 2010; 35 (2): 121-123

    Abstract

    We report what we believe to be the first demonstration of a laser-driven fiber optic gyroscope (FOG) built with an air-core fiber. Its phase noise is measured to be 130 murad/ radicalHz. When the sensing fiber is replaced with a conventional fiber, this figure drops to 12 murad/ radicalHz. Comparison between these values suggests that the air-core fiber gyro is most likely not limited solely by backscattering noise but by reflections at the solid-core/air-core interface. By minimizing additional noise sources and reducing the air-core fiber loss to its theoretical limit (approximately 0.1 dB/km), we predict that the backscattering noise of the laser-driven air-core FOG will drop below the level of current FOGs. Compared with commercial FOGs, this FOG will exhibit a lower noise, improved thermal and mean-wavelength stability, and reduced magnetic-field sensitivity.

    View details for Web of Science ID 000273879200010

    View details for PubMedID 20081941

  • Optical resonances created by photonic transitions APPLIED PHYSICS LETTERS Yu, Z., Fan, S. 2010; 96 (1)

    View details for DOI 10.1063/1.3279130

    View details for Web of Science ID 000273473200008

  • Directional Photofluidization Lithography for Nanoarchitectures with Controlled Shapes and Sizes NANO LETTERS Lee, S., Shin, J., Lee, Y., Fan, S., Park, J. 2010; 10 (1): 296-304

    Abstract

    Highly ordered metallic nanostructures have attracted an increasing interest in nanoscale electronics, photonics, and spectroscopic imaging. However, methods typically used for fabricating metallic nanostructures, such as direct writing and template-based nanolithography, have low throughput and are, moreover, limited to specific fabricated shapes such as holes, lines, and prisms, respectively. Herein, we demonstrate directional photofluidization lithography (DPL) as a new method to address the aforementioned problems of current nanolithography. The key idea of DPL is the use of photoreconfigurable polymer arrays to be molded in metallic nanostructures instead of conventional colloids or cross-linked polymer arrays. The photoreconfiguration of polymers by directional photofluidization allows unprecedented control over the sizes and shapes of metallic nanostructures. Besides the capability for precise control of structural features, DPL ensures scalable, parallel, and cost-effective processing, highly compatible with high-throughput fabrication. Therefore, DPL can expand not only the potential for specific metallic nanostructure applications but also large-scale innovative nanolithography.

    View details for DOI 10.1021/nl903570c

    View details for Web of Science ID 000273428700050

    View details for PubMedID 20017565

  • Magnetic field enhancement beyond the skin-depth limit Shin, J., Park, N., Fan, S., Lee, Y., Sadwick, L. P., OSullivan, C. M. SPIE-INT SOC OPTICAL ENGINEERING. 2010

    View details for DOI 10.1117/12.841805

    View details for Web of Science ID 000285577600011

  • Slow and Stopped Light in Coupled Resonator Systems PHOTONIC MICRORESONATOR RESEARCH AND APPLICATIONS Fan, S., Sandhu, S., Otey, C. R., Povinelli, M. L., Chremmos, Schwelb, O., Uzunoglu, N. 2010; 156: 165-180
  • Enhancement of optics-to-THz conversion efficiency by metallic slot waveguides Conference on Nonlinear Frequency Generation and Conversion - Materials, Devices, and Applications IX Ruan, Z., Veronis, G., Vodopyanov, K. L., Fejer, M. M., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2010

    View details for DOI 10.1117/12.840088

    View details for Web of Science ID 000284935000027

  • DESIGN AND GROWTH OF III-V NANOWIRE SOLAR CELL ARRAYS ON LOW COST SUBSTRATES 35th IEEE Photovoltaic Specialists Conference Gu, A., Huo, Y., Hu, S., Sarmiento, T., Pickett, E., Liang, D., Li, S., Lin, A., Thombare, S., Yu, Z., Fan, S., McIntyre, P., Cui, Y., Harris, J. IEEE. 2010: 2034–2037
  • Transparent electrode designs based on optimal nano-patterning of metallic films Conference on Plasmonics: Metallic Nanostructures and Their Optical Properties VIII Catrysse, P. B., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2010

    View details for DOI 10.1117/12.860998

    View details for Web of Science ID 000285828300028

  • Coupled resonator gyroscopes: what works and what does not Conference on Advances in Slow and Fast Light III Terrel, M. A., Digonnet, M. J., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2010

    View details for DOI 10.1117/12.848637

    View details for Web of Science ID 000284309300006

  • Suspended photonic crystal slabs for biosensing Conference On Frontiers in Pathogen Detection - From Nanosensors to Systems El Beheiry, M., Liu, V., Fan, S., Levi, O. SPIE-INT SOC OPTICAL ENGINEERING. 2010

    View details for DOI 10.1117/12.842945

    View details for Web of Science ID 000285577200016

  • Absorber and emitter for solar thermophotovoltaic systems to achieve efficiency exceeding the Shockley-Queisser limit Optics Express Rephaeli, E., Fan, S., H. 2010; 17 (17): 15145-15159
  • Full inversion of a two-level atom with a single-photon pulse in one-dimensional geometries Physical Review A Rephaeli, E., Shen, J., T., Fan, S., H. 2010; 82 (3)
  • Experimental demonstration of an all-optical analogue to the superradiance effect in an on-chip photonic crystal resonator system Physical Review B Fan, S., H., Pan, J., Sandhu, S., Huo et. al., Y., J. 2010; 81 (4)
  • Exponential suppression of thermal conductance using coherent transport and heterostructures Physical Review B Lau, W., T., Shen, J., T., Fan, S., H. 2010; 82 (11)
  • Enhancement of optical absorption in thin-film organic solar cells through the excitation of plasmonic modes in metallic gratings Applied Physics Letters Fan, S., H., Min, C., J., Li, J., Veronis et. al., G. 2010; 96 (13)

    View details for DOI 133302 10.1063/1.3377791

  • Tuning the coherent interaction in an on-chip photonic-crystal waveguide-resonator system Applied Physics Letters Pan, J., Huo, Y., J., Sandhu et. al., S. 2010; 97 (10)

    View details for DOI 101102 10.1063/1.3486686

  • Input-output formalism for few-photon transport in one-dimensional nanophotonic waveguides coupled to a qubit Physical Review A Fan, S., H., Kocabas, S., E., shen, J., T. 2010; 82 (6)
  • Thermal Rectification through Vacuum Physical Review Letters Otey, C., R., Lau, W., T., Fan, S., H. 2010; 104 (15)
  • Superscattering of Light from Subwavelength Nanostructures Physical Review Letters Ruan, Z., C., Fan, S., H. 2010; 105 (1)
  • Elements for Plasmonic Nanocircuits with Three-Dimensional Slot Waveguides Advanced Materials Cai, W., S., Shin, W., Fan et. al., S., H. 2010; 22 (45): 5120-+

    View details for DOI 10.1002/adma.201001440

  • Quantum critical coupling conditions for zero single-photon transmission through a coupled atom-resonator-waveguide system Physical Review A Shen, J., T., Fan, S., H. 2010; 82 (2)
  • Photonic Band Structure of Dispersive Metamaterials Formulated as a Hermitian Eigenvalue Problem Physical Review Letters Raman, A., Fan, S., H. 2010; 104 (8)
  • Optical resonances created by photonic transitions Applied Physics Letters Yu, Z., F., Fan, S., H. 2010; 96 (1)

    View details for DOI 011108 10.1063/1.3279130

  • Mapping local optical densities of states in silicon photonic structures with nanoscale electron spectroscopy Physical Review B Fan, S., H., Cha, J., J., Yu, Z., F., Smith et. al., E. 2010; 81 (11)
  • Enhancing optical switching with coherent control Applied Physics Letters Sandhu, S., Povinelli, M., L., Fan, S., H. 2010; 96 (23)

    View details for DOI 231108 10.1063/1.3449572

  • Deep-subwavelength focusing and steering of light in an aperiodic metallic waveguide array Conference on Integrated Optics - Devices, Materials, and Technologies XIV Verslegers, L., Catrysse, P. B., Yu, Z., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2010

    View details for DOI 10.1117/12.842692

    View details for Web of Science ID 000284398000020

  • Optimizing Nano-patterned Metal Films for Use as Transparent Electrodes in Optoelectronic Devices Conference on Lasers and Electro-Optics (CLEO)/Quantum Electronics and Laser Science Conference (QELS) Catrysse, P. B., Fan, S. IEEE. 2010
  • Dynamic Photonic Structure for Integrated Photonics Conference on Optoelectronic Integrated Circuits XII Yu, Z., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2010

    View details for DOI 10.1117/12.846032

    View details for Web of Science ID 000284396700018

  • LIMIT OF NANOPHOTONIC LIGHT-TRAPPING IN SOLAR CELLS 35th IEEE Photovoltaic Specialists Conference Yu, Z., Raman, A., Fan, S. IEEE. 2010: 76–78
  • Fundamental Limit of Nanophotonic Light-trapping in Solar Cells Conference on Lasers and Electro-Optics (CLEO)/Quantum Electronics and Laser Science Conference (QELS) Yu, Z., Raman, A., Fan, S. IEEE. 2010
  • Phase Front Design with Metallic Pillar Arrays Conference on Lasers and Electro-Optics (CLEO)/Quantum Electronics and Laser Science Conference (QELS) Verslegers, L., Catrysse, P. B., Yu, Z., Shin, W., Ruan, Z., Fan, S. IEEE. 2010
  • Temporal coupled-mode theory for the Fano resonance in light scattering and its applications Conference on Lasers and Electro-Optics (CLEO)/Quantum Electronics and Laser Science Conference (QELS) Ruan, Z., Fan, S. IEEE. 2010
  • Fundamental Limit of Nanophotonic Light-trapping in Solar Cells Conference on Next Generation (Nano) Photonic and Cell Technologies for Solar Energy Conversion Yu, Z., Raman, A., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2010

    View details for DOI 10.1117/12.861457

    View details for Web of Science ID 000285841900015

  • Experimental demonstration of an all-optical analogue to the superradiance effect in an on-chip photonic crystal resonator system PHYSICAL REVIEW B Pan, J., Sandhu, S., Huo, Y., Stuhrmann, N., Povinelli, M. L., Harris, J. S., Fejer, M. M., Fan, S. 2010; 81 (4)
  • Resonance-enhanced optical forces between coupled photonic crystal slabs OPTICS EXPRESS Liu, V., Povinelli, M., Fan, S. 2009; 17 (24): 21897-21909

    Abstract

    The behaviors of lateral and normal optical forces between coupled photonic crystal slabs are analyzed. We show that the optical force is periodic with displacement, resulting in stable and unstable equilibrium positions. Moreover, the forces are strongly enhanced by guided resonances of the coupled slabs. Such enhancement is particularly prominent near dark states of the system, and the enhancement effect is strongly dependent on the types of guided resonances involved. These structures lead to enhancement of light-induced pressure over larger areas, in a configuration that is directly accessible to externally incident, free-space optical beams.

    View details for Web of Science ID 000272229400061

    View details for PubMedID 19997434

  • Two-electron transport in a quantum waveguide having a single Anderson impurity NEW JOURNAL OF PHYSICS Shen, J., Fan, S. 2009; 11
  • Large single-molecule fluorescence enhancements produced by a bowtie nanoantenna NATURE PHOTONICS Kinkhabwala, A., Yu, Z., Fan, S., Avlasevich, Y., Muellen, K., Moerner, W. E. 2009; 3 (11): 654-657
  • Universal features of coherent photonic thermal conductance in multilayer photonic band gap structures PHYSICAL REVIEW B Lau, W. T., Shen, J., Fan, S. 2009; 80 (15)
  • Wave-vector space picture for radiationless focusing and beaming OPTICS LETTERS Intaraprasonk, V., Fan, S. 2009; 34 (19): 2967-2969

    Abstract

    Radiationless interference of an electromagnetic wave occurs in the near field when the feature sizes of the waves are at the deep subwavelength scale. We present the propagation in such a regime using a wave-vector space picture. Using this picture, we reproduce the condition to achieve near-field focusing. We also design the initial field distribution needed for near-field beaming, where an intensity distribution maintains its shape as it propagates. We conclude the discussion by proposing a possible implementation of the near-field beaming scheme.

    View details for Web of Science ID 000270366800030

    View details for PubMedID 19794784

  • Side-coupled cavity model for surface plasmon-polariton transmission across a groove OPTICS EXPRESS Liu, J. S., White, J. S., Fan, S., Brongersma, M. L. 2009; 17 (20): 17837-17848

    Abstract

    We demonstrate that the transmission properties of surface plasmon-polaritons (SPPs) across a rectangular groove in a metallic film can be described by an analytical model that treats the groove as a side-coupled cavity to propagating SPPs on the metal surface. The coupling efficiency to the groove is quantified by treating it as a truncated metal-dielectric-metal (MDM) waveguide. Finite-difference frequency-domain (FDFD) simulations and mode orthogonality relations are employed to derive the basic scattering coefficients that describe the interaction between the relevant modes in the system. The modeled SPP transmission and reflection intensities show excellent agreement with full-field simulations over a wide range of groove dimensions, validating this intuitive model. The model predicts the sharp transmission minima that occur whenever an incident SPP resonantly couples to the groove. We also for the first time show the importance of evanescent, reactive MDM SPP modes to the transmission behavior. SPPs that couple to this mode are resonantly enhanced upon reflection from the bottom of the groove, leading to high field intensities and sharp transmission minima across the groove. The resonant behavior exhibited by the grooves has a number of important device applications, including SPP mirrors, filters, and modulators.

    View details for Web of Science ID 000270295300065

    View details for PubMedID 19907571

  • Ring-coupled Mach-Zehnder interferometer optimized for sensing APPLIED OPTICS Terrel, M., Digonnet, M. J., Fan, S. 2009; 48 (26): 4874-4879

    Abstract

    We demonstrate numerically that the theoretical maximum sensitivity of a ring-coupled Mach-Zehnder interferometer (MZI) optimized as a sensor is about 30% greater than the optimized sensitivity of a conventional single-bus ring sensor with an identical ring perimeter and loss. The ring-coupled MZI sensor also achieves its greater sensitivity with a 25% lower circulating power, which is useful for the suppression of undesirable nonlinear effects.

    View details for Web of Science ID 000270117600004

    View details for PubMedID 19745847

  • Classification of the Core Modes of Hollow-Core Photonic-Bandgap Fibers IEEE JOURNAL OF QUANTUM ELECTRONICS Aghaie, K. Z., Dangui, V., Digonnet, M. J., Fan, S., Kino, G. S. 2009; 45 (9): 1192-1200
  • Performance comparison of slow-light coupled-resonator optical gyroscopes LASER & PHOTONICS REVIEWS Terrel, M., Digonnet, M. J., Fan, S. 2009; 3 (5): 452-465
  • Overcoming gain-bandwidth product constraint in slow light Raman amplification with the use of light-stopping schemes APPLIED PHYSICS LETTERS Sandhu, S., Povinelli, M. L., Fan, S. 2009; 95 (8)

    View details for DOI 10.1063/1.3211126

    View details for Web of Science ID 000269723200003

  • Planar metallic nanoscale slit lenses for angle compensation APPLIED PHYSICS LETTERS Verslegers, L., Catrysse, P. B., Yu, Z., Fan, S. 2009; 95 (7)

    View details for DOI 10.1063/1.3211875

    View details for Web of Science ID 000269288300012

  • Absorber and emitter for solar thermophotovoltaic systems to achieve efficiency exceeding the Shockley-Queisser limit OPTICS EXPRESS Rephaeli, E., Fan, S. 2009; 17 (17): 15145-15159

    Abstract

    We present theoretical considerations as well as detailed numerical design of absorber and emitter for Solar Thermophotovoltaics (STPV) applications. The absorber, consisting of an array of tungsten pyramids, was designed to provide near-unity absorptivity over all solar wavelengths for a wide angular range, enabling it to absorb light effectively from solar sources regardless of concentration. The emitter, a tungsten slab with Si/SiO(2) multilayer stack, provides a sharp emissivity peak at the solar cell band-gap while suppressing emission at lower frequencies. We show that, under a suitable light concentration condition, and with a reasonable area ratio between the emitter and absorber, a STPV system employing such absorber-emitter pair and a single-junction solar cell can attain efficiency that exceeds the Shockley-Queisser limit.

    View details for Web of Science ID 000269232800069

    View details for PubMedID 19687992

  • Enhancement of optics-to-THz conversion efficiency by metallic slot waveguides OPTICS EXPRESS Ruan, Z., Veronis, G., Vodopyanov, K. L., Fejer, M. M., Fan, S. 2009; 17 (16): 13502-13515

    Abstract

    A metallic slot waveguide, with a dielectric strip embedded within, is investigated for the purpose of enhancing the optics-to-THz conversion efficiency using the difference-frequency generation (DFG) process. To describe the frequency conversion process in such lossy waveguides, a fully-vectorial coupled-mode theory is developed. Using the coupled-mode theory, we outline the basic theoretical requirements for efficient frequency conversion, which include the needs to achieve large coupling coefficients, phase matching, and low propagation loss for both the optical and THz waves. Following these requirements, a metallic waveguide is designed by considering the trade-off between modal confinement and propagation loss. Our numerical calculation shows that the conversion efficiency in these waveguide structures can be more than one order of magnitude larger than what has been achieved using dielectric waveguides. Based on the distinct impact of the slot width on the optical and THz modal dispersion, we propose a two-step method to realize the phase matching for general pump wavelengths.

    View details for Web of Science ID 000268843700027

    View details for PubMedID 19654758

  • Modeling of Plasmonic Waveguide Components and Networks JOURNAL OF COMPUTATIONAL AND THEORETICAL NANOSCIENCE Veronis, G., Kocabas, S. E., Miller, D. A., Fan, S. 2009; 6 (8): 1808-1826
  • Measurements of the Birefringence and Verdet Constant in an Air-Core Fiber JOURNAL OF LIGHTWAVE TECHNOLOGY Wen, H., Terrel, M. A., Kim, H. K., Digonnet, M. J., Fan, S. 2009; 27 (15): 3194-3201
  • Deep-Subwavelength Focusing and Steering of Light in an Aperiodic Metallic Waveguide Array PHYSICAL REVIEW LETTERS Verslegers, L., Catrysse, P. B., Yu, Z., Fan, S. 2009; 103 (3)

    Abstract

    We consider an aperiodic array of coupled metallic waveguides with varying subwavelength widths. For an incident plane wave, we numerically demonstrate that a focus of as small as one-hundredth of a wavelength can be achieved for a focal distance that is much longer than the wavelength. Moreover, the focusing behavior can be controlled by changing either the incident wavelength or the angle of incidence, thus providing the capability of nanoscale beam steering. We show that the behavior of such subwavelength focusing can be understood using Hamiltonian optics.

    View details for DOI 10.1103/PhysRevLett.103.033902

    View details for Web of Science ID 000268088300027

    View details for PubMedID 19659280

  • Understanding the dispersion of coaxial plasmonic structures through a connection with the planar metal-insulator-metal geometry APPLIED PHYSICS LETTERS Catrysse, P. B., Fan, S. 2009; 94 (23)

    View details for DOI 10.1063/1.3148692

    View details for Web of Science ID 000266977100011

  • Capturing light pulses into a pair of coupled photonic crystal cavities APPLIED PHYSICS LETTERS Otey, C. R., Povinelli, M. L., Fan, S. 2009; 94 (23)

    View details for DOI 10.1063/1.3141485

    View details for Web of Science ID 000266977100009

  • Optical isolation based on nonreciprocal phase shift induced by interband photonic transitions APPLIED PHYSICS LETTERS Yu, Z., Fan, S. 2009; 94 (17)

    View details for DOI 10.1063/1.3127531

    View details for Web of Science ID 000265738700016

  • Three-Dimensional Metamaterials with an Ultrahigh Effective Refractive Index over a Broad Bandwidth PHYSICAL REVIEW LETTERS Shin, J., Shen, J., Fan, S. 2009; 102 (9)

    Abstract

    The authors introduce a general mechanism, based on electrostatic and magnetostatic considerations, for designing three-dimensional isotropic metamaterials that possess an enhanced refractive index over an extremely large frequency range. The mechanism allows nearly independent control of effective electric permittivity and magnetic permeability without the use of resonant elements.

    View details for DOI 10.1103/PhysRevLett.102.093903

    View details for Web of Science ID 000263911900022

    View details for PubMedID 19392520

  • Extraordinary optical absorption through subwavelength slits OPTICS LETTERS White, J. S., Veronis, G., Yu, Z., Barnard, E. S., Chandran, A., Fan, S., Brongersma, M. L. 2009; 34 (5): 686-688

    Abstract

    We report on the ability of resonant plasmonic slits to efficiently concentrate electromagnetic energy into a nanoscale volume of absorbing material placed inside or directly behind the slit. This gives rise to extraordinary optical absorption characterized by an absorption enhancement factor that well exceeds the enhancements seen for extraordinary optical transmission through slits. A semianalytic Fabry-Perot model for the resonant absorption is developed and shown to quantitatively agree with full-field simulations. We show that absorption enhancements of nearly 1000% can be realized at 633 nm for slits in aluminum films filled with silicon. This effect can be utilized in a wide range of applications, including high-speed photodetectors, optical lithography and recording, and biosensors.

    View details for Web of Science ID 000264522400046

    View details for PubMedID 19252593

  • Complete optical isolation created by indirect interband photonic transitions NATURE PHOTONICS Yu, Z., Fan, S. 2009; 3 (2): 91-94
  • Theory of single-photon transport in a single-mode waveguide. II. Coupling to a whispering-gallery resonator containing a two-level atom PHYSICAL REVIEW A Shen, J., Fan, S. 2009; 79 (2)
  • Theory of single-photon transport in a single-mode waveguide. I. Coupling to a cavity containing a two-level atom PHYSICAL REVIEW A Shen, J., Fan, S. 2009; 79 (2)
  • Optical Absorption Enhancement in Amorphous Silicon Nanowire and Nanocone Arrays NANO LETTERS Zhu, J., Yu, Z., Burkhard, G. F., Hsu, C., Connor, S. T., Xu, Y., Wang, Q., McGehee, M., Fan, S., Cui, Y. 2009; 9 (1): 279-282

    Abstract

    Hydrogenated amorphous Si (a-Si:H) is an important solar cell material. Here we demonstrate the fabrication of a-Si:H nanowires (NWs) and nanocones (NCs), using an easily scalable and IC-compatible process. We also investigate the optical properties of these nanostructures. These a-Si:H nanostructures display greatly enhanced absorption over a large range of wavelengths and angles of incidence, due to suppressed reflection. The enhancement effect is particularly strong for a-Si:H NC arrays, which provide nearly perfect impedance matching between a-Si:H and air through a gradual reduction of the effective refractive index. More than 90% of light is absorbed at angles of incidence up to 60 degrees for a-Si:H NC arrays, which is significantly better than NW arrays (70%) and thin films (45%). In addition, the absorption of NC arrays is 88% at the band gap edge of a-Si:H, which is much higher than NW arrays (70%) and thin films (53%). Our experimental data agree very well with simulation. The a-Si:H nanocones function as both absorber and antireflection layers, which offer a promising approach to enhance the solar cell energy conversion efficiency.

    View details for DOI 10.1021/nl802886y

    View details for Web of Science ID 000262519100052

    View details for PubMedID 19072061

  • Stopping Light via Dynamic Tuning of Coupled Resonators SLOW LIGHT: SCIENCE AND APPLICATIONS Fan, S., Povinelli, M. L., Khurgin, J. B., Tucker, R. S. 2009; 140: 277-289
  • PLASMONIC SLOT WAVEGUIDES PLASMONIC NANOGUIDES AND CIRCUITS Veronis, G., Fan, S., Bozhevolnyi, S. I. 2009: 159-187
  • Complete optical isolation created by indirect interband photonic transitions Conference on Silicon Photonics IV Yu, Z., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2009

    View details for DOI 10.1117/12.807739

    View details for Web of Science ID 000285748000022

  • Ultra-Small Coherent Thermal Conductance Using Multi-Layer Photonic Crystal Conference on Photonic and Phononic Crystal Materials and Devices IX Lau, W. T., Shen, J., Veronis, G., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2009

    View details for DOI 10.1117/12.808432

    View details for Web of Science ID 000285746400022

  • Coupled resonator optical waveguide sensors: sensitivity and the role of slow light Conference on Fiber Optic Sensors and Applications VI Terrel, M. A., Digonnet, M. J., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2009

    View details for DOI 10.1117/12.833477

    View details for Web of Science ID 000299088400016

  • Large enhancement of second-harmonic generation in subwavelength metal-dielectric-metal plasmonic waveguides Conference on Integrated Optics - Devices, Materials, and Technologies XIII Veronis, G., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2009

    View details for DOI 10.1117/12.809727

    View details for Web of Science ID 000285748100025

  • Theory of single-photon transport in a single-mode waveguide. II. Coupling to a whispering-gallery resonator containing a two-level atom Physical Review A Shen, J., T., Fan, S., H. 2009; 79 (2)
  • Overcoming gain-bandwidth product constraint in slow light Raman amplification with the use of light-stopping schemes Applied Physics Letters Sandhu, S., Povinelli, M., L., Fan et. al., S., H. 2009; 95 (8)

    View details for DOI 081103 10.1063/1.3211126

  • Two-electron transport in a quantum waveguide having a single Anderson impurity New Journal of Physics Shen, J., T., Fan, S., H. 2009; 11
  • Planar metallic nanoscale slit lenses for angle compensation Applied Physics Letters Fan, S., H., Verslegers, L., Catrysse, P., B., Yu et. al., Z., F. 2009; 95 (7)

    View details for DOI 071112 10.1063/1.3211875

  • Deep-Subwavelength Focusing and Steering of Light in an Aperiodic Metallic Waveguide Array Physical Review Letters Fan, S., H., Verslegers, L., Catrysse, P., B., Yu et. al., Z., F. 2009; 103 (3)
  • Universal features of coherent photonic thermal conductance in multilayer photonic band gap structures Physical Review B Lau, W., T., Shen, J., T., Fan, S., H. 2009; 80 (15)
  • Understanding the dispersion of coaxial plasmonic structures through a connection with the planar metal-insulator-metal geometry Applied Physics Letters Catrysse, P., B., Fan, S., H. 2009; 94 (23)

    View details for DOI 231111 10.1063/1.3148692

  • Three-Dimensional Metamaterials with an Ultrahigh Effective Refractive Index over a Broad Bandwidth Physical Review Letters Shin, J., Shen, J., T., Fan, S., H. 2009; 102 (9)
  • Theory of single-photon transport in a single-mode waveguide. I. Coupling to a cavity containing a two-level atom Physical Review A Shen, J., T., Fan, S., H. 2009; 79 (2)
  • Optical isolation based on nonreciprocal phase shift induced by interband photonic transitions Applied Physics Letters Yu, Z., F., Fan, S., H. 2009; 94 (17)

    View details for DOI 171116 10.1063/1.3127531

  • Capturing light pulses into a pair of coupled photonic crystal cavities Applied Physics Letters Otey, C., R., Povinelli, M., L., Fan, S., H. 2009; 94 (23)

    View details for DOI 231109 10.1063/1.3141485

  • Modal analysis and coupling in metal-insulator-metal waveguides Physical Review B Fan, S., H., Kocabas, S., E., Veronis, G., Miller et. al., D., A. B. 2009; 79 (3)
  • Simple Analytical Expression for the Dispersion of Plasmonic Structures with Coaxial Geometry Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2009) Catrysse, P. B., Fan, S. IEEE. 2009: 1838–1839
  • Integrated nanophotonics: dynamic optical isolation, and nanoscale far-field focusing in aperiodic plasmonic waveguide array 22nd Annual Meeting of the IEEE-Photonics-Society Fan, S., Yu, Z., Verslegers, L., Catrysse, P. IEEE. 2009: 646–647
  • Light Trapping With a Few Cavities Conference on Advances in Slow and Fast Light II Otey, C. R., Povinelli, M. L., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2009

    View details for DOI 10.1117/12.816328

    View details for Web of Science ID 000285377800018

  • Performance Limitation of a Coupled Resonant Optical Waveguide Gyroscope JOURNAL OF LIGHTWAVE TECHNOLOGY Terrel, M. A., Digonnet, M. J., Fan, S. 2009; 27 (1-4): 47-54
  • Dynamics of optical modes in modulated photonic structures IEEE/LEOS Winter Topicals Meeting Fan, S., Yu, Z., Otey, C., Povinelli, M. IEEE. 2009: 106–107
  • Optical Resonances Created by Photonic Transitions Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2009) Yu, Z., Fan, S. IEEE. 2009: 1327–1328
  • Planar Lenses Based on Nanoscale Slit Arrays in a Metallic Film Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2009) Verslegers, L., Catrysse, P. B., Yu, Z., White, J. S., Barnard, E. S., Brongersma, M. L., Fan, S. IEEE. 2009: 3224–3225
  • Minimizing Coherent Thermal Conductance Using Multi-Layer Photonic Crystal Heterostructures Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2009) Lau, W. T., Shen, J., Fan, S. IEEE. 2009: 2035–2036
  • Modal analysis and coupling in metal-insulator-metal waveguides PHYSICAL REVIEW B Kocabas, S. E., Veronis, G., Miller, D. A., Fan, S. 2009; 79 (3)
  • Planar Lenses Based on Nanoscale Slit Arrays in a Metallic Film NANO LETTERS Verslegers, L., Catrysse, P. B., Yu, Z., White, J. S., Barnard, E. S., Brongersma, M. L., Fan, S. 2009; 9 (1): 235-238

    Abstract

    We experimentally demonstrate planar lenses based on nanoscale slit arrays in a metallic film. Our lens structures consist of optically thick gold films with micron-size arrays of closely spaced, nanoscale slits of varying widths milled using a focused ion beam. We find excellent agreement between electromagnetic simulations of the design and confocal measurements on manufactured structures. We provide guidelines for lens design and show how actual lens behavior deviates from simple theory.

    View details for DOI 10.1021/nl802830y

    View details for Web of Science ID 000262519100044

    View details for PubMedID 19053795

  • Analysis of guided-resonance-based polarization beam splitting in photonic crystal slabs JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION Kilic, O., Fan, S., Solgaard, O. 2008; 25 (11): 2680-2692

    Abstract

    We present an analysis of the phase and amplitude responses of guided resonances in a photonic crystal slab. Through this analysis, we obtain the general rules and conditions under which a photonic crystal slab can be employed as a general elliptical polarization beam splitter, separating an incoming beam equally into its two orthogonal constituents, so that half the power is reflected in one polarization state, and half the power is transmitted in the other state. We show that at normal incidence a photonic crystal slab acts as a dual quarter-wave retarder in which the fast and slow axes are switched for reflection and transmission. We also analyze the case where such a structure operates at oblique incidences. As a result we show that the effective dielectric constant of the photonic crystal slab imposes the Brewster angle as a boundary, separating two ranges of angles with different mechanisms of polarization beam splitting. We show that the diattenuation can be tuned from zero to one to make the structure a circular or linear polarization beam splitter. We verify our analytical analysis through finite-difference time-domain simulations and experimental measurements at infrared wavelengths.

    View details for Web of Science ID 000261520700008

    View details for PubMedID 18978845

  • Completely Capturing Light Pulses in a Few Dynamically Tuned Microcavities JOURNAL OF LIGHTWAVE TECHNOLOGY Otey, C. R., Povinelli, M. L., Fan, S. 2008; 26 (21-24): 3784-3793
  • Protein microarrays with carbon nanotubes as multicolor Raman labels NATURE BIOTECHNOLOGY Chen, Z., Tabakman, S. M., Goodwin, A. P., Kattah, M. G., Daranciang, D., Wang, X., Zhang, G., Li, X., Liu, Z., Utz, P. J., Jiang, K., Fan, S., Dai, H. 2008; 26 (11): 1285-1292

    Abstract

    The current sensitivity of standard fluorescence-based protein detection limits the use of protein arrays in research and clinical diagnosis. Here, we use functionalized, macromolecular single-walled carbon nanotubes (SWNTs) as multicolor Raman labels for highly sensitive, multiplexed protein detection in an arrayed format. Unlike fluorescence methods, Raman detection benefits from the sharp scattering peaks of SWNTs with minimal background interference, affording a high signal-to-noise ratio needed for ultra-sensitive detection. When combined with surface-enhanced Raman scattering substrates, the strong Raman intensity of SWNT tags affords protein detection sensitivity in sandwich assays down to 1 fM--a three-order-of-magnitude improvement over most reports of fluorescence-based detection. We use SWNT Raman tags to detect human autoantibodies against proteinase 3, a biomarker for the autoimmune disease Wegener's granulomatosis, diluted up to 10(7)-fold in 1% human serum. SWNT Raman tags are not subject to photobleaching or quenching. By conjugating different antibodies to pure (12)C and (13)C SWNT isotopes, we demonstrate multiplexed two-color SWNT Raman-based protein detection.

    View details for DOI 10.1038/nbt.1501

    View details for Web of Science ID 000260832200024

    View details for PubMedID 18953353

  • Transmission Line and Equivalent Circuit Models for Plasmonic Waveguide Components IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS Kocabas, S. E., Veronis, G., Miller, D. A., Fan, S. 2008; 14 (6): 1462-1472
  • Multiplexed multicolor Raman imaging of live cells with isotopically modified single walled carbon nanotubes JOURNAL OF THE AMERICAN CHEMICAL SOCIETY Liu, Z., Li, X., Tabakman, S. M., Jiang, K., Fan, S., Dai, H. 2008; 130 (41): 13540-?

    Abstract

    We show that single walled carbon nanotubes (SWNTs) with different isotope compositions exhibit distinct Raman G-band peaks and can be used for multiplexed multicolor Raman imaging of biological systems. Cancer cells with specific receptors are selectively labeled with three differently "colored" SWNTs conjugated with various targeting ligands including Herceptin (anti-Her2), Erbitux (anti-Her1), and RGD peptide, allowing for multicolor Raman imaging of cells in a multiplexed manner. SWNT Raman signals are highly robust against photobleaching, allowing long-term imaging and tracking. With narrow peak features, SWNT Raman signals are easily differentiated from the autofluorescence background. The SWNT Raman excitation and scattering photons are in the near-infrared region, which is the most transparent optical window for biological systems in vitro and in vivo. Thus, SWNTs are novel Raman tags promising for multiplexed biological detection and imaging.

    View details for DOI 10.1021/ja806242t

    View details for Web of Science ID 000259924000017

    View details for PubMedID 18803379

    View details for PubMedCentralID PMC2617744

  • Tungsten black absorber for solar light with wide angular operation range APPLIED PHYSICS LETTERS Rephaeli, E., Fan, S. 2008; 92 (21)

    View details for DOI 10.1063/1.2936997

    View details for Web of Science ID 000256303500007

  • Aligning microcavity resonances in silicon photonic-crystal slabs using laser-pumped thermal tuning APPLIED PHYSICS LETTERS Pan, J., Huo, Y., Yamanaka, K., Sandhu, S., Scaccabarozzi, L., Timp, R., Povinelli, M. L., Fan, S., Fejer, M. M., Harris, J. S. 2008; 92 (10)

    View details for DOI 10.1063/1.2896615

    View details for Web of Science ID 000253989300114

  • Tuning coherent radiative thermal conductance in multilayer photonic crystals APPLIED PHYSICS LETTERS Lau, W. T., Shen, J., Veronis, G., Fan, S., Braun, P. V. 2008; 92 (10)

    View details for DOI 10.1063/1.2890433

    View details for Web of Science ID 000253989300106

  • Crosstalk between three-dimensional plasmonic slot waveguides OPTICS EXPRESS Veronis, G., Fan, S. 2008; 16 (3): 2129-2140

    Abstract

    We investigate in detail the crosstalk between plasmonic slot waveguides. We show that the coupling behavior of deep subwavelength three-dimensional (3-D) plasmonic slot waveguides is very different from the one of two-dimensional (2-D) metal-dielectric-metal (MDM) plasmonic waveguides. While in the 2-D case the coupling occurs only through the metal, in the 3-D case the coupling occurs primarily through the dielectric, in which the evanescent tail is much larger compared to the one in the metal. Thus, in most cases the coupling between 3-D plasmonic slot waveguides is much stronger than the coupling between the corresponding 2-D MDM plasmonic waveguides. Such strong coupling can be exploited to form directional couplers using plasmonic slot waveguides. On the other hand, with appropriate design, the crosstalk between 3-D plasmonic slot waveguides can be reduced even below the crosstalk levels of 2-D MDM plasmonic waveguides, without significantly affecting their modal size and attenuation length. Thus, 3-D plasmonic slot waveguides can be used for ultradense integration of optoelectronic components.

    View details for Web of Science ID 000252932500081

    View details for PubMedID 18542293

  • Gain-induced switching in metal-dielectric-metal plasmonic waveguides APPLIED PHYSICS LETTERS Yu, Z., Veronis, G., Fan, S., Brongersma, M. L. 2008; 92 (4)

    View details for DOI 10.1063/1.2839324

    View details for Web of Science ID 000252860400017

  • One-way electromagnetic waveguide formed at the interface between a plasmonic metal under a static magnetic field and a photonic crystal PHYSICAL REVIEW LETTERS Yu, Z., Veronis, G., Wang, Z., Fan, S. 2008; 100 (2)

    Abstract

    We demonstrate theoretically the existence of one-way electromagnetic modes in a waveguide formed between a semi-infinite photonic crystal structure and a semi-infinite metal region under a static magnetic field. Such a waveguide provides a frequency range where only one propagating direction is allowed. In this frequency range, disorder-induced scattering is completely suppressed. Such a waveguide also modifies the basic properties of waveguide-cavity interaction.

    View details for DOI 10.1103/PhysRevLett.100.023902

    View details for Web of Science ID 000252471200031

    View details for PubMedID 18232868

  • GaN-based two-dimensional surface-emitting photonic crystal lasers with AlN/GaN distributed Bragg reflector APPLIED PHYSICS LETTERS Lu, T., Chen, S., Lin, L., Kao, T., Kao, C., Yu, P., Kuo, H., Wang, S., Fan, S. 2008; 92 (1)

    View details for DOI 10.1063/1.2831716

    View details for Web of Science ID 000252284200029

  • Tuning Coherent Radiative Thermal Conductance in Multilayer Photonic Crystals Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2008) Lau, W. T., Shen, J., Veronis, G., Fan, S. IEEE. 2008: 3026–3027
  • Photonic crystal theory: Temporal coupled-mode formalism OPTICAL FIBER TELECOMMUNICATIONS V A: COMPONENTS AND SUBSYSTEMS Fan, S., Kaminow, I. P., Li, T., Willner, A. E. 2008: 431-454
  • Gain-induced switching in metal-dielectric-metal plasmonic waveguides Yu, Z., Veronis, G., Brongersma, M. L., Fan, S., Greiner, C. M., Waechter, C. A. SPIE-INT SOC OPTICAL ENGINEERING. 2008

    View details for DOI 10.1117/12.764052

    View details for Web of Science ID 000254226600016

  • Properties of three-dimensional plasmonic slot waveguides Conference on Plasmonics - Metallic Nanostructures and their Optical Properties VI Veronis, G., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2008

    View details for DOI 10.1117/12.794322

    View details for Web of Science ID 000260664900015

  • Spatial coherence of the thermal electromagnetic field in the vicinity of a dielectric slab Conference on Photonic Crystal Materials and Devices VII Lau, W. T., Shen, J., Veronis, G., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2008

    View details for DOI 10.1117/12.761909

    View details for Web of Science ID 000254740000003

  • Fabrication and Performance of GaN-based Two Dimensional Photonic Crystal Surface Emitting Lasers IEEE 21st International Semiconductor Laser Conference Lu, T., Kao, T., Chen, S., Liu, T., Yu, P., Kuo, H., Wang, S., Fan, S. IEEE. 2008: 187–188
  • Tungsten black absorber for solar light with wide angular operation range Applied Physics Letters Rephaeli, E., Fan, S. 2008; 92 (21)

    View details for DOI 211107 10.1063/1.2936997

  • Propagating plasmonic mode in nanoscale apertures and its implications for extraordinary transmission Journal of Nanophotonics Catrysse, P., B., Fan, S., H. 2008; 2

    View details for DOI 021790 10.1117/1.2890424

  • Gain-induced switching in metal-dielectric-metal plasmonic waveguides Applied Physics Letters Yu, Z., F., Veronis, G., Fan et. al., S., H. 2008; 92 (4)

    View details for DOI 041117 10.1063/1.2839324

  • GaN-based two-dimensional surface-emitting photonic crystal lasers with AlN/GaN distributed Bragg reflector Applied Physics Letters Fan, S., H., Lu, T., C., Chen, S., W., Lin et. al., L., F. 2008; 92 (1)

    View details for DOI 011129 10.1063/1.2831716

  • Aligning microcavity resonances in silicon photonic-crystal slabs using laser-pumped thermal tuning Applied Physics Letters Fan, S., H., Pan, J., Huo, Y., Yamanaka et. al., K. 2008; 92 (10)

    View details for DOI 103114 10.1063/1.2896615

  • One-way electromagnetic waveguide formed at the interface between a plasmonic metal under a static magnetic field and a photonic crystal Physical Review Letters Fan, S., H., Yu, Z., F., Veronis, G., Wang et. al., Z. 2008; 100 (2)
  • Tuning coherent radiative thermal conductance in multilayer photonic crystals Applied Physics Letters Fan, S., H., Lau, W., T., Shen, J., T., Veronis et. al., G. 2008; 92 (10)

    View details for DOI 103106 10.1063/1.2890433

  • Stopping and time-reversing a light pulse using dynamic loss-tuning of coupled-resonator delay lines Conference on Laser Resonators and Beam Control X Sandhu, S., Povinelli, M. L., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2008

    View details for DOI 10.1117/12.773815

    View details for Web of Science ID 000255510400011

  • Crosstalk between three-dimensional plasmonic slot waveguides Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2008) Veronis, G., Fan, S. IEEE. 2008: 3571–3572
  • Deep-Subwavelength Coaxial Waveguides with a Hollow Core Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2008) Catrysse, P. B., Fan, S. IEEE. 2008: 3567–3568
  • Propagating plasmonic mode in nanoscale apertures and its implications for extraordinary transmission JOURNAL OF NANOPHOTONICS Catrysse, P. B., Fan, S. 2008; 2

    View details for DOI 10.1117/1.2890424

    View details for Web of Science ID 000262931600013

  • Dispersionless Three-dimensional Metamaterial with a Very High Refractive Index Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2008) Shin, J., Shen, J., Fan, S. IEEE. 2008: 3131–3132
  • Strongly correlated multiparticle transport in one dimension through a quantum impurity PHYSICAL REVIEW A Shen, J., Fan, S. 2007; 76 (6)
  • Stopping and time reversing a light pulse using dynamic loss tuning of coupled-resonator delay lines OPTICS LETTERS Sandhu, S., Povinelli, M. L., Fan, S. 2007; 32 (22): 3333-3335

    Abstract

    We introduce a light-stopping process that uses dynamic loss tuning in coupled-resonator delay lines. We demonstrate via numerical simulations that increasing the loss of selected resonators traps light in a zero group velocity mode concentrated in the low-loss portions of the delay line. The large dynamic range achievable for loss modulation should increase the light-stopping bandwidth relative to previous approaches based on refractive index tuning.

    View details for Web of Science ID 000251747600037

    View details for PubMedID 18026298

  • Enlarging the bandwidth of nanoscale propagating plasmonic modes in deep-subwavelength cylindrical holes APPLIED PHYSICS LETTERS Catrysse, P. B., Fan, S. 2007; 91 (18)

    View details for DOI 10.1063/1.2803849

    View details for Web of Science ID 000250643600018

  • Three-dimensional electromagnetic metamaterials that homogenize to uniform non-Maxwellian media PHYSICAL REVIEW B Shin, J., Shen, J., Fan, S. 2007; 76 (11)
  • Modes of subwavelength plasmonic slot waveguides JOURNAL OF LIGHTWAVE TECHNOLOGY Veronis, G., Fan, S. 2007; 25 (9): 2511-2521
  • The nonlinear effect from the interplay between the nonlinearity and the supercollimation of photonic crystal APPLIED PHYSICS LETTERS Jiang, X., Zhou, C., Yu, X., Fan, S., Soljacic, M., Joannopoulos, J. D. 2007; 91 (3)

    View details for DOI 10.1063/1.2739413

    View details for Web of Science ID 000248194000005

  • Spatial coherence of the thermal electromagnetic field in the vicinity of a dielectric slab PHYSICAL REVIEW E Lau, W. T., Shen, J., Veronis, G., Fan, S. 2007; 76 (1)

    Abstract

    We present the analytic calculation of the cross-spectral density tensor of a thermally radiative planar dielectric slab in extreme near-field, intermediate near-field, and far-field zones. We show that the spatial coherence of the thermal field exhibits distinct features in these zones. At a given wavelength lambda , the coherence length is many orders of magnitude smaller than lambda in the extreme near-field zone, and is roughly lambda/2 in the far-field zone. In the intermediate near-field zone, the coherence length can be much longer than lambda/2 if the loss is small. The physical origin of the short-ranged spatial coherence in the extreme near-field zone is the spatially fluctuating surface charges at the air-dielectric interface. We also demonstrate that in the intermediate near-field zone, the long-ranged spatial coherence is induced by the waveguide modes of the dielectric slab. When the loss is small, the long-ranged coherence falls off approximately as 1/square root x , in contrast to 1/x for a blackbody radiator, where x refers to displacement parallel to the slab surface.

    View details for DOI 10.1103/PhysRevE.76.016601

    View details for Web of Science ID 000248552600058

    View details for PubMedID 17677579

  • A germanium inverse woodpile structure with a large photonic band gap ADVANCED MATERIALS Garcia-Santamaria, F., Xu, M., Lousse, V., Fan, S., Braun, P. V., Lewis, J. A. 2007; 19 (12): 1567-?
  • Polarization controller for hollow-core fiber OPTICS LETTERS Terrel, M., Digonnet, M. J., Fan, S. 2007; 32 (11): 1524-1526

    Abstract

    We demonstrate a universal polarization controller for hollow-core fibers, a simple device consisting of three twisted fiber sections that makes use of the inherent birefringence of the air-core fiber. The device 5% bandwidth at 1550 nm is calculated from measured data to be approximately 13 nm.

    View details for Web of Science ID 000247756600060

    View details for PubMedID 17546176

  • Manipulating light with photonic crystals 7th International Conference on Electrical Transport and Optical Properties of Inhomogeneous Media (ETOPIM-7) Fan, S. ELSEVIER SCIENCE BV. 2007: 221–28
  • Enhancing or suppressing self-focusing in nonlinear photonic crystals APPLIED PHYSICS LETTERS Yu, X., Jiang, X., Fan, S. 2007; 90 (16)

    View details for DOI 10.1063/1.2724905

    View details for Web of Science ID 000245870400024

  • Strongly correlated two-photon transport in a one-dimensional waveguide coupled to a two-level system PHYSICAL REVIEW LETTERS Shen, J., Fan, S. 2007; 98 (15)

    Abstract

    We show that two-photon transport is strongly correlated in one-dimensional waveguide coupled to a two-level system. The exact S matrix is constructed using a generalized Bethe-ansatz technique. We show that the scattering eigenstates of this system include a two-photon bound state that passes through the two-level system as a composite single particle. Also, the two-level system can induce effective attractive or repulsive interactions in space for photons. This general procedure can be applied to the Anderson model as well.

    View details for DOI 10.1103/PhysRevLett.98.153003

    View details for Web of Science ID 000245691400023

    View details for PubMedID 17501344

  • One-way total reflection with one-dimensional magneto-optical photonic crystals APPLIED PHYSICS LETTERS Yu, Z., Wang, Z., Fan, S. 2007; 90 (12)

    View details for DOI 10.1063/1.2716359

    View details for Web of Science ID 000245135800033

  • Theoretical investigation of compact couplers between dielectric slab waveguides and two-dimensional metal-dielectric-metal plasmonic waveguides OPTICS EXPRESS Veronis, G., Fan, S. 2007; 15 (3): 1211-1221

    Abstract

    We theoretically investigate the properties of compact couplers between high-index contrast dielectric slab waveguides and two-dimensional metal-dielectric-metal subwavelength plasmonic waveguides. We show that a coupler created by simply placing a dielectric waveguide terminated flat at the exit end of a plasmonic waveguide can be designed to have a transmission efficiency of ~70% at the optical communication wavelength. We also show that the transmission efficiency of the couplers can be further increased by using optimized multisection tapers. In both cases the transmission response is broadband. In addition, we investigate the properties of a Fabry-Perot structure in which light is coupled in and out of a plasmonic waveguide sandwiched between dielectric waveguides. Finally, we discuss potential fabrication processes for structures that demonstrate the predicted effects.

    View details for Web of Science ID 000244682200051

    View details for PubMedID 19532350

  • Near-complete transmission through subwavelength hole arrays in phonon-polaritonic thin films PHYSICAL REVIEW B Catrysse, P. B., Fan, S. 2007; 75 (7)
  • Overexpression of NDRG1 is an indicator of poor prognosis in hepatocellular carcinoma MODERN PATHOLOGY Chua, M., Sun, H., Cheung, S. T., Mason, V., Higgins, J., Ross, D. T., Fan, S. T., So, S. 2007; 20 (1): 76-83

    Abstract

    Hepatocellular carcinoma is a highly lethal cancer that typically has poor prognosis. Prognostic markers can help in its clinical management and in understanding the biology of poor prognosis. Through an earlier gene expression study, we identified N-Myc downregulated gene 1 (NDRG1) to be significantly highly expressed in hepatocellular carcinoma compared to nontumor liver. As NDRG1 is a differentiation-related gene with putative metastasis suppressor activity, we investigated the clinical significance of its overexpression. Quantitative real-time polymerase chain reaction using an independent set of patient samples confirmed the significant overexpression of NDRG1 in hepatocellular carcinoma compared to nontumor liver samples (P<0.001). Additionally, high levels of NDRG1 transcript correlated with shorter overall survival (P<0.001), late tumor stage (P=0.001), vascular invasion (P=0.003), large tumor size (P=0.011), and high Edmondson-Steiner histological grade (P=0.005). Using immunohistochemistry, NDRG1 protein was found to be significantly overexpressed in hepatocellular carcinoma samples compared to nontumor liver or cirrhotic and benign liver lesions (P<0.001). Among the hepatocellular carcinoma samples, those which are moderately and poorly differentiated express higher levels of NDRG1 protein than those which are well-differentiated (P<0.005). Additionally, hepatocellular carcinomas with vascular invasion also express elevated levels of NDRG1 protein compared to those without vascular invasion (significant at P<0.005). Our results suggest NDRG1 to be a likely tumor marker for hepatocellular carcinoma, the overexpression of which is correlated with tumor differentiation, vascular invasion, and overall survival. Its significantly elevated expression in hepatocellular carcinoma could be a useful indicator of tumor aggressiveness and therefore patient prognosis.

    View details for DOI 10.1038/modpathol.3800711

    View details for Web of Science ID 000243005000010

    View details for PubMedID 17170744

  • OVERVIEW OF SIMULATION TECHNIQUES FOR PLASMONIC DEVICES SURFACE PLASMON NANOPHOTONICS Veronis, G., Fan, S., Brongersma, M. L., Kik, P. G. 2007; 131: 169-182
  • Three-dimensional electromagnetic metamaterials that homogenize to uniform non-Maxwellian media Physical Review B Shin, J., Shen, J., T., Fan, S. 2007; 76 (11)
  • The nonlinear effect from the interplay between the nonlinearity and the supercollimation of photonic crystal Applied Physics Letters Fan, S., H., Jiang, X., Y., Zhou, C., H., Yu et. al., X., F. 2007; 91 (3)

    View details for DOI 031105 10.1063/1.2739413

  • Enhancing or suppressing self-focusing in nonlinear photonic crystals Applied Physics Letters Yu, X., F., Jiang, X., Y., Fan, S. 2007; 90 (16)

    View details for DOI 161124 10.1063/1.2724905

  • Stopping single photons in one-dimensional circuit quantum electrodynamics systems Physical Review B Fan, S., H., Shen, J., T., Povinelli, M., L., Sandhu et. al., S. 2007; 75 (3)
  • Strongly correlated multiparticle transport in one dimension through a quantum impurity Physical Review A Shen, J., T., Fan, S. 2007; 76 (6)
  • One-way total reflection with one-dimensional magneto-optical photonic crystals Applied Physics Letters Yu, Z., F., Wang, Z., Fan, S., H. 2007; 90 (12)

    View details for DOI 121133 10.1063/1.2716359

  • Slow light - Dynamic photon storage Nature Physics Yanik, M., F., Fan, S. 2007; 3 (6): 372-374

    View details for DOI 10.1038/nphys630

  • Spatial coherence of the thermal electromagnetic field in the vicinity of a dielectric slab Physical Review E Fan, S., H., Lau, W., T., Shen, J., T., Veronis et. al., G. 2007; 76 (1)
  • Modeling nonlinear optical phenomena in nanophotonics Journal of Lightwave Technology Bravo-Abad, J., Fan, S., Johnson et. al., S., G. 2007; 25 (9): 2539-2546

    View details for DOI 10.1109/jlt.2007.903547

  • Enlarging the bandwidth of nanoscale propagating plasmonic modes in deep-subwavelength cylindrical holes Applied Physics Letters Catrysse, P., B., Fan, S., H. 2007; 91 (18)

    View details for DOI 181118 10.1063/1.2803849

  • A germanium inverse woodpile structure with a large photonic band gap Advanced Materials Fan, S., H., Garcia-Santamaria, F., Xu, M., J., Lousse, V. 2007; 19 (12): 1567-+

    View details for DOI 10.1002/adma.200602906

  • Strongly correlated two-photon transport in a one-dimensional waveguide coupled to a two-level system Physical Review Letters Shen, J., T., Fan, S., H. 2007; 98 (15)
  • Compact couplers between dielectric and plasmonic slot waveguides Conference on Integrated Optics - Devices, Materials, and Technology XI Veronis, G., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2007

    View details for DOI 10.1117/12.701562

    View details for Web of Science ID 000246061700024

  • Near-complete transmission through subwavelength hole arrays in phonon-polaritonic thin films Physical Review B Catrysse, P., B., Fan, S., H. 2007; 75 (7)
  • One-way electromagnetic waveguide 20th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society Yu, Z., Veronis, G., Wang, Z., Fan, S. IEEE. 2007: 278–279
  • Stopping single photons in one-dimensional circuit quantum electrodynamics systems PHYSICAL REVIEW B Shen, J., Povinelli, M. L., Sandhu, S., Fan, S. 2007; 75 (3)
  • Transmission enhancement and suppression by subwavelength hole arrays in polaritonic films Conference on Photonic Crystal Materials and Devices VI Catrysse, P. B., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2007

    View details for DOI 10.1117/12.702917

    View details for Web of Science ID 000246368900003

  • One-way waveguide and strong photon-photon interaction in nanophotonic structures IEEE/LEOS International Conference on Optical MEMS and Nanophotonics Fan, S., Shen, J., Yu, Z., Veronis, G., Wang, Z. IEEE. 2007: 181–182
  • Coherent few-photon quantum transport in one-dimensional systems Conference on Advanced Optical and Quantum Memories and Computing IV Shen, J., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2007

    View details for DOI 10.1117/12.716467

    View details for Web of Science ID 000246396000016

  • Radiation loss of coupled-resonator waveguides in photonic-crystal slabs Conference on Photonic Crystal Materials and Devices VI Povinelli, A. L., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2007

    View details for DOI 10.1117/12.704597

    View details for Web of Science ID 000246368900014

  • New properties of light in metamaterials Conference on Metamaterials II Fan, S., Shin, J., Shen, J. SPIE-INT SOC OPTICAL ENGINEERING. 2007

    View details for DOI 10.1117/12.724178

    View details for Web of Science ID 000250370100006

  • Dynamically-tuned microresonator complexes Conference on Laser Resonators and Beam Control IX Povinelli, M. L., Sandhu, S., Shen, J., Yanik, M. F., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2007

    View details for DOI 10.1117/12.714597

    View details for Web of Science ID 000245978400002

  • Phonon polariton reflectance spectra in a silicon carbide membrane hole array 20th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society Provine, J., Catrysse, P. B., Roper, C. S., Maboudian, R., Fan, S., Howe, R. T. IEEE. 2007: 466–467
  • Compact couplers between dielectric and metal-dielectric-metal plasmonic waveguides Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference Veronis, G., Shin, W., Fan, S. IEEE. 2007: 895–896
  • Optical Characterization and Sensitivity Evaluation of Guided-Resonances in Photonic Crystal Slabs for Biosensing Applications Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference Levi, O., Lee, M. M., Zhang, J., Lousse, V., Brueck, S. R., Fan, S., Harris, J. S. IEEE. 2007: 993–994
  • Sensitivity analysis of a photonic crystal structure for index-of-refraction sensing Conference on Nanoscale Imaging, Spectroscopy, Sensing, and Actuation for Biomedical Applications IV Levi, O., Lee, M. M., Zhang, J., Lousse, V., Brueck, S. R., Fan, S., Harris, J. S. SPIE-INT SOC OPTICAL ENGINEERING. 2007

    View details for DOI 10.1117/12.705670

    View details for Web of Science ID 000245976200016

  • Design of mid-infrared photodetectors enhanced by surface plasmons on grating structures Conference on Integrated Optics - Devices, Materials, and Technology XI Yu, Z., Veronis, G., Brongersma, M. L., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2007

    View details for DOI 10.1117/12.698016

    View details for Web of Science ID 000246061700022

  • Extraordinary transmission through a poly-SiC membrane with subwavelength hole arrays IEEE/LEOS International Conference on Optical MEMS and Nanophotonics Provine, J., Catrysse, P. B., Roper, C., Maboudian, R., Fan, S., Howe, R. T. IEEE. 2007: 157–158
  • Enhanced second-harmonic generation in AlGaAs/AlxOy tightly confining waveguides and resonant cavities OPTICS LETTERS Scaccabarozzi, L., Fejer, M. M., Huo, Y., Fan, S., Yu, X., Harris, J. S. 2006; 31 (24): 3626-3628

    Abstract

    We demonstrate second-harmonic generation (SHG) from sub-micrometer-sized AlGaAs/AlxOy artificially birefringent waveguides. The normalized conversion efficiency is the highest ever reported. We further enhanced the SHG using a waveguide-embedded cavity formed by dichroic mirrors. Resonant enhancements as high as approximately 10x were observed. Such devices could be potentially used as highly efficient, ultracompact frequency converters in integrated photonic circuits.

    View details for Web of Science ID 000242560400022

    View details for PubMedID 17130925

  • Advances in theory of photonic crystals JOURNAL OF LIGHTWAVE TECHNOLOGY Fan, S., Yanik, M. F., Wang, Z., Sandhu, S., Povinelli, M. L. 2006; 24 (12): 4493-4501
  • Dichroic mirror embedded in a submicrometer waveguide for enhanced resonant nonlinear optical devices OPTICS LETTERS Scaccabarozzi, L., Fejer, M. M., Huo, Y., Fan, S., Yu, X., Harris, J. S. 2006; 31 (22): 3285-3287

    Abstract

    We report the design, fabrication and characterization of novel dichroic mirrors embedded in a tightly confining AlGaAs/Al(x)O(y) waveguide. Reflection at the first-harmonic wavelength as high as 93% is achieved, while high transmission is maintained at the second-harmonic wavelength. The measured cavity spectrum is in excellent agreement with finite-difference time-domain simulations. Such a mirror is essential for achieving resonant enhancement of second-harmonic generation.

    View details for Web of Science ID 000241799700022

    View details for PubMedID 17072398

  • Radiation loss of coupled-resonator waveguides in photonic-crystal slabs APPLIED PHYSICS LETTERS Povinelli, M. L., Fan, S. 2006; 89 (19)

    View details for DOI 10.1063/1.2387131

    View details for Web of Science ID 000241960400014

  • Cut-through metal slit array as an anisotropic metamaterial film IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS Shin, J., Shen, J., Catrysse, P. B., Fan, S. 2006; 12 (6): 1116-1122
  • Conditions for designing single-mode air-core waveguides in three-dimensional photonic crystals APPLIED PHYSICS LETTERS Lousse, V., Shin, J., Fan, S. 2006; 89 (16)

    View details for DOI 10.1063/1.2362983

    View details for Web of Science ID 000241405200003

  • Design of midinfrared photodetectors enhanced by surface plasmons on grating structures APPLIED PHYSICS LETTERS Yu, Z., Veronis, G., Fan, S., Brongersma, M. L. 2006; 89 (15)

    View details for DOI 10.1063/1.2360896

    View details for Web of Science ID 000241247900016

  • All-angle negative refraction and evanescent wave amplification using one-dimensional metallodielectric photonic crystals APPLIED PHYSICS LETTERS Shin, H., Fan, S. 2006; 89 (15)

    View details for DOI 10.1063/1.2360187

    View details for Web of Science ID 000241247900002

  • Suppressing the effect of disorders using time-reversal symmetry breaking in magneto-optical photonic crystals: An illustration with a four-port circulator PHOTONICS AND NANOSTRUCTURES-FUNDAMENTALS AND APPLICATIONS Wang, Z., Fan, S. 2006; 4 (3): 132-140
  • Dynamically tuned coupled-resonator delay lines can be nearly dispersion free OPTICS LETTERS Sandhu, S., Povinelli, M. L., Yanik, M. F., Fan, S. 2006; 31 (13): 1985-1987

    Abstract

    We investigate dispersion effects in dynamically tuned, coupled-resonator delay lines. Provided that the system is tuned to a zero-bandwidth state, a signal can be delayed indefinitely with almost no dispersion. We present a theoretical analysis of such a light-stopping system and verify the results using numerical simulations.

    View details for Web of Science ID 000238494600015

    View details for PubMedID 16770407

  • Experimental realization of an on-chip all-optical analogue to electromagnetically induced transparency PHYSICAL REVIEW LETTERS Xu, Q. F., Sandhu, S., Povinelli, M. L., Shakya, J., Fan, S. H., Lipson, M. 2006; 96 (12)

    Abstract

    We provide the first experimental observation of structure tuning of the electromagnetically induced transparency-like spectrum in integrated on-chip optical resonator systems. The system consists of coupled silicon ring resonators with 10 microm diameter on silicon, where the coherent interference between the two coupled resonators is tuned. We measured a transparency-resonance mode with a quality factor of 11,800.

    View details for DOI 10.1103/PhysRevLett.96.123901

    View details for Web of Science ID 000236467000020

    View details for PubMedID 16605904

  • Anomalous modal structure in a waveguide with a photonic crystal core OPTICS LETTERS Yu, X. F., Lau, W. T., Fan, S. H. 2006; 31 (6): 742-744

    Abstract

    We analyze a dielectric waveguide with a photonic crystal core. Using constant frequency contour analysis, we show that the modal behavior of this structure is drastically different from that of a conventional slab waveguide. In particular, at a given frequency the lowest-order guided mode can have an odd symmetry or can have more than one nodal plane in its field distribution. Also, there exist several single-mode regions with a different modal profile in each region. Finally, a single-mode waveguide for the fundamental mode with a large core and strong confinement can be realized. All these behaviors are confirmed by our three-dimensional finite-difference time-domain simulations.

    View details for Web of Science ID 000235833400022

    View details for PubMedID 16544609

  • Systematic photonic crystal device design: Global and local optimization and sensitivity analysis IEEE JOURNAL OF QUANTUM ELECTRONICS Jiao, Y., Fan, S. H., Miller, D. A. 2006; 42 (3-4): 266-279
  • Model dispersive media in finite-difference time-domain method with complex-conjugate pole-residue pairs IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS Han, M. H., DUTTON, R. W., Fan, S. H. 2006; 16 (3): 119-121
  • All-angle negative refraction for surface plasmon waves using a metal-dielectric-metal structure PHYSICAL REVIEW LETTERS Shin, H., Fan, S. H. 2006; 96 (7)

    Abstract

    We show that a metal-dielectric-metal structure can function as a negative refraction lens for surface plasmon waves on a metal surface. The structure is uniform with respect to a plane of incidence and operates at the optical frequency range. Using three-dimensional finite-difference time-domain simulations, we demonstrate the imaging operation of the structure with realistic material parameters including dispersions and losses. Our design should facilitate the demonstration of many novel effects associated with negative refraction on chip at optical wavelength ranges. In addition, this structure provides a new way of controlling the propagation of surface plasmons, which are important for nanoscale manipulation of optical waves.

    View details for DOI 10.1103/PhysRevLett.96.073907

    View details for Web of Science ID 000235554100034

    View details for PubMedID 16606095

  • Direct-write assembly of three-dimensional photonic crystals: Conversion of polymer scaffolds to silicon hollow-woodpile structures ADVANCED MATERIALS Gratson, G. M., Garcia-Santamaria, F., Lousse, V., Xu, M. J., Fan, S. H., Lewis, J. A., Braun, P. V. 2006; 18 (4): 461-?
  • Waveguides in inverted opal photonic crystals OPTICS EXPRESS Lousse, V., Fan, S. H. 2006; 14 (2): 866-878

    Abstract

    Waveguiding phenomena are investigated in an inverted opal photonic crystal made of interpenetrating air spheres, coated with amorphous Ge. Here we focus on the complete gap between the 8th and the 9th band, since a projected band analysis reveals that it is difficult to use the large lower incomplete gap for guiding purposes. Two kinds of line defects are analyzed within this photonic structure, with the plane-wave expansion method. The first one consists of an air cylinder in the Gamma-K direction. It gives rise to a large number of defect modes in the bandgap. Most of these modes have large field components at the surface. The second defect is an array of air spheres, also along the Gamma-K direction. This is shown to avoid the surface-like modes and sustain only two modes associated with different polarizations, in the frequency range of interest. The air mode waveguiding bandwidth reaches up to 113 nm centered at a wavelength of 1.5 microm.

    View details for Web of Science ID 000235012000047

    View details for PubMedID 19503406

  • Guided modes supported by plasmonic films with a periodic arrangement of subwavelength slits APPLIED PHYSICS LETTERS Catrysse, P. B., Veronis, G., Shin, H., Shen, J. T., Fan, S. 2006; 88 (3)

    View details for DOI 10.1063/1.2164905

    View details for Web of Science ID 000234757100001

  • Integrated biomedical nanosensor using guided resonance in photonic crystal structures Conference on Nanobiophotonics and Biomedical Applications III Levi, O., Suh, W., Lee, M. M., Zhang, J., Brueck, S. R., Fan, S., Harris, J. S. SPIE-INT SOC OPTICAL ENGINEERING. 2006

    View details for DOI 10.1117/12.647312

    View details for Web of Science ID 000237699500014

  • Frequency domain modeling of nanophotonic devices PHOTONICS: DESIGN, TECHNOLOGY, AND PACKAGING II Veronis, G., Fan, S. H. 2006; 6038

    View details for DOI 10.1117/12.651341

    View details for Web of Science ID 000236542100021

  • Plasmonic films with a periodic arrangement of sub-wavelength slits Conference on Photonic Crystal Materials and Devices IV Catrysse, P. B., Veronis, G., Shen, J., Shin, H., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2006

    View details for DOI 10.1117/12.648510

    View details for Web of Science ID 000238247900032

  • Tunable terahertz Bloch oscillations in graded-index photonic crystals Conference on Photonic Crystal Materials and Devices IV Lousse, V., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2006

    View details for DOI 10.1117/12.646604

    View details for Web of Science ID 000238247900031

  • Subwavelength plasmonic waveguide structures based on slots in thin metal films INTEGRATED OPTICS: DEVICES, MATERIALS, AND TECHNOLOGIES X Veronis, G., Fan, S. 2006; 6123

    View details for DOI 10.1117/12.646789

    View details for Web of Science ID 000237286300006

  • Direct-write assembly of three-dimensional photonic crystals: Conversion of polymer scaffolds to silicon hollow-woodpile structures Advanced Materials Fan, S., H., Gratson, G., M., Garcia-Santamaria, F., Lousse et. al., V. 2006; 18 (4): 461-+

    View details for DOI 10.1002/adma.200501447

  • Radiation loss of coupled-resonator waveguides in photonic-crystal slabs Applied Physics Letters Povinelli, M., L., Fan, S., H. 2006; 89 (19)

    View details for DOI 191114 10.1063/1.2387131

  • All-angle negative refraction for surface plasmon waves using a metal-dielectric-metal structure Physical Review Letters Shin, H., Fan, S., H. 2006; 96 (7)
  • Design of midinfrared photodetectors enhanced by surface plasmons on grating structures Applied Physics Letters Yu, Z., F., Veronis, G., Fan et. al., S., H. 2006; 89 (15)

    View details for DOI 151116 10.1063/1.2360896

  • Cut-through metal slit array as an anisotropic metamaterial film Ieee Journal of Selected Topics in Quantum Electronics Fan, S., H., Shin, J., Shen, J., T., Catrysse et. al., P., B. 2006; 12 (6)
  • Conditions for designing single-mode air-core waveguides in three-dimensional photonic crystals Applied Physics Letters Lousse, V., Shin, J., Fan, S., H. 2006; 89 (16)

    View details for DOI 161103 10.1063/1.2362983

  • Waveguides in inverted opal photonic crystals Optics Express Lousse, V., Fan, S., H. 2006; 14 (2): 866-878

    View details for DOI 10.1364/opex.14.000866

  • Guided modes supported by plasmonic films with a periodic arrangement of subwavelength slits Applied Physics Letters Fan, S., H., Catrysse, P., B., Veronis, G., Shin et. al., H. 2006; 88 (3)

    View details for DOI 031101 10.1063/1.2164905

  • Air-bridged photonic crystal slabs at visible and near-infrared wavelengths Physical Review B Fan, S., H., Crozier, K., B., Lousse, V., Kilic et. al., O. 2006; 73 (11)
  • Experimental realization of an on-chip all-optical analogue to electromagnetically induced transparency Physical Review Letters Fan, S., H., Xu, Q., F., Sandhu, S., Povinelli et. al., M., L. 2006; 96 (12)
  • All-angle negative refraction and evanescent wave amplification using one-dimensional metallodielectric photonic crystals Applied Physics Letters Shin, H., C., Fan, S., H. 2006; 89 (15)

    View details for DOI 151102 10.1063/1.2360187

  • A polarization controller for air-core photonic-bandgap fiber Conference on Optical Fiber Communications/National Fiber Optic Engineers Conference Terrel, M., Digonnet, M., Fan, S. OPTICAL SOC AMERICA. 2006: 681–683
  • Dynamically-tuned coupled-resonator delay lines can be nearly dispersion free Conference on Advanced Optical and Quantum Memories and Computing III Sandhu, S., Povinelli, M. L., Yanik, M. F., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2006
  • Photonic crystals for communications: Stopping light and miniaturized non-reciprocal devices Conference on Optical Fiber Communications/National Fiber Optic Engineers Conference Fan, S., Yanik, M. F., Wang, Z., Povinelle, M., Sandhu, S. OPTICAL SOC AMERICA. 2006: 2119–2121
  • Controlling diffraction and waveguide modes by exploiting spatial dispersions in photonic crystals Conference on Photonic Crystal Materials and Devices IV Fan, S., Yu, X., Shin, J., Lau, W. T. SPIE-INT SOC OPTICAL ENGINEERING. 2006

    View details for DOI 10.1117/12.649564

    View details for Web of Science ID 000238247900025

  • Magneto-optical circulator in two-dimensional photonic crystals Conference on Photonic Crystal Materials and Devices IV Wang, Z., Fan, S. SPIE-INT SOC OPTICAL ENGINEERING. 2006

    View details for DOI 10.1117/12.646874

    View details for Web of Science ID 000238247900009

  • Guided subwavelength plasmonic mode supported by a slot in a thin metal film OPTICS LETTERS Veronis, G., Fan, S. H. 2005; 30 (24): 3359-3361

    Abstract

    We demonstrate the existence of a bound optical mode supported by a slot in a thin metallic film deposited on a substrate, with slot dimensions much smaller than the wavelength. The modal size is almost completely dominated by the near field of the slot. Consequently, the size is very small compared with the wavelength, even when the dispersion relation of the mode approaches the light line of the surrounding media. In addition, the group velocity of this mode is close to the speed of light in the substrate, and its propagation length is tens of micrometers at the optical communication wavelength.

    View details for Web of Science ID 000233827000033

    View details for PubMedID 16389831

  • Understanding air-core photonic-bandgap fibers: Analogy to conventional fibers JOURNAL OF LIGHTWAVE TECHNOLOGY Digonnet, M. J., Kim, H. K., Kino, G. S., Fan, S. H. 2005; 23 (12): 4169-4177
  • Coherent single photon transport in a one-dimensional waveguide coupled with superconducting quantum bits PHYSICAL REVIEW LETTERS Shen, J. T., Fan, S. H. 2005; 95 (21)

    Abstract

    A recent theoretical analysis and experimental results show that interesting transport properties of a single microwave photon emerge when a quantum bit in a cavity is coupled to a one-dimensional waveguide. Here we adopt a real-space model Hamiltonian to give a unified approach which accounts for the experimental results, and make new predictions on the properties of single photon transport, such as the general Fano line shape, symmetric vacuum Rabi splitting for a leaky cavity at resonance, and a one-photon switching capability.

    View details for DOI 10.1103/PhysRevLett.95.213001

    View details for Web of Science ID 000233362100018

    View details for PubMedID 16384136

  • Propagating modes in subwavelength cylindrical holes 49th International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication Catrysse, P. B., Shin, H., Fan, S. H. A V S AMER INST PHYSICS. 2005: 2675–78

    View details for DOI 10.1116/1.2130344

    View details for Web of Science ID 000234613200077

  • Bends and splitters in metal-dielectric-metal subwavelength plasmonic waveguides APPLIED PHYSICS LETTERS Veronis, G., Fan, S. H. 2005; 87 (13)

    View details for DOI 10.1063/1.2056594

    View details for Web of Science ID 000232060200002

  • Conditions for self-collimation in three-dimensional photonic crystals OPTICS LETTERS Shin, J. W., Fan, S. H. 2005; 30 (18): 2397-2399

    Abstract

    We introduce the theoretical criterion for achieving three-dimensional self-collimation of light in a photonic crystal. Based on this criterion, we numerically demonstrate a body-center-cubic structure that supports wide-angle self-collimation and is directly compatible with the recently developed holographic fabrication technique. We further show that both bends and beam splitters can be introduced into this structure by the use of interfaces.

    View details for Web of Science ID 000231964600017

    View details for PubMedID 16196331

  • Wannier basis design and optimization of a photonic crystal waveguide crossing IEEE PHOTONICS TECHNOLOGY LETTERS Jiao, Y., Mingaleev, S. F., Schillinger, M., Miller, D. A., Fan, S., Busch, K. 2005; 17 (9): 1875-1877
  • Coherent photon transport from spontaneous emission in one-dimensional waveguides OPTICS LETTERS Shen, J. T., Fan, S. H. 2005; 30 (15): 2001-2003

    Abstract

    A two-level system coupled to a one-dimensional continuum is investigated. By using a real-space model Hamiltonian, we show that spontaneous emission can coherently interfere with the continuum modes and gives interesting transport properties. The technique is applied to various related problems with different configurations, and analytical solutions are given.

    View details for Web of Science ID 000230714400029

    View details for PubMedID 16092246

  • Tunable terahertz Bloch oscillations in chirped photonic crystals PHYSICAL REVIEW B Lousse, V., Fan, S. 2005; 72 (7)
  • Dynamic photonic structures: Stopping, storage, and time reversal of light STUDIES IN APPLIED MATHEMATICS Yanik, M. F., Fan, S. H. 2005; 115 (2): 233-253
  • Displacement sensing using evanescent tunneling between guided resonances in photonic crystal slabs JOURNAL OF APPLIED PHYSICS Suh, W., Solgaard, O., Fan, S. 2005; 98 (3)

    View details for DOI 10.1063/1.1999031

    View details for Web of Science ID 000231246100002

  • Optical circulators in two-dimensional magneto-optical photonic crystals OPTICS LETTERS Wang, Z., Fan, S. H. 2005; 30 (15): 1989-1991

    Abstract

    We propose an optical circulator formed of a magneto-optical cavity in a 2D photonic crystal