Kiyoul Yang

All Publications

• 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

• Quantum optics of soliton microcombs NATURE PHOTONICS Guidry, M. A., Lukin, D. M., Yang, K., Trivedi, R., Vuckovic, J. 2021

  View details for DOI 10.1038/s41566-021-00901-z

  View details for Web of Science ID 000730888100001

• Inverse-Designed Photonic Crystal Circuits for Optical Beam Steering ACS PHOTONICS Vercruysse, D., Sapra, N., Yang, K., Vuckovic, J. 2021; 8 (10): 3085-3093

  View details for DOI 10.1021/acsphotonics.1c01119

  View details for Web of Science ID 000710954200034

• 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

• Inverse Spectral Design of Kerr Microcomb Pulses Lucas, E., Yu, S., Ahn, G., Yang, K., Vuckovic, J., Papp, S. B., Ilchenko, V. S., Armani, A. M., Sheldakova, J. V., Kudryashov, A. V., Paxton, A. H. SPIE-INT SOC OPTICAL ENGINEERING. 2021

  View details for DOI 10.1117/12.2576439

  View details for Web of Science ID 000695307500001

• Optical parametric oscillation in silicon carbide nanophotonics OPTICA Guidry, M. A., Yang, K., Lukin, D. M., Markosyan, A., Yang, J., Fejer, M. M., Vuckovic, J. 2020; 7 (9): 1139–42

  View details for DOI 10.1364/OPTICA.394138

  View details for Web of Science ID 000575440600015

• 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

  View details for DOI 10.1038/s41566-020-0606-0

  View details for Web of Science ID 000521525600003

• Earth rotation measured by a chip-scale ring laser gyroscope NATURE PHOTONICS Lai, Y., Suh, M., Lu, Y., Shen, B., Yang, Q., Wang, H., Li, J., Lee, S., Yang, K., Vahala, K. 2020

  View details for DOI 10.1038/s41566-020-0588-y

  View details for Web of Science ID 000514050900002

• On-chip integrated laser-driven particle accelerator. Science (New York, N.Y.) Sapra, N. V., Yang, K. Y., Vercruysse, D. n., Leedle, K. J., Black, D. S., England, R. J., Su, L. n., Trivedi, R. n., Miao, Y. n., Solgaard, O. n., Byer, R. L., Vučkovicć, J. n. 2020; 367 (6473): 79–83

  Abstract

  Particle accelerators represent an indispensable tool in science and industry. However, the size and cost of conventional radio-frequency accelerators limit the utility and reach of this technology. Dielectric laser accelerators (DLAs) provide a compact and cost-effective solution to this problem by driving accelerator nanostructures with visible or near-infrared pulsed lasers, resulting in a 104 reduction of scale. Current implementations of DLAs rely on free-space lasers directly incident on the accelerating structures, limiting the scalability and integrability of this technology. We present an experimental demonstration of a waveguide-integrated DLA that was designed using a photonic inverse-design approach. By comparing the measured electron energy spectra with particle-tracking simulations, we infer a maximum energy gain of 0.915 kilo-electron volts over 30 micrometers, corresponding to an acceleration gradient of 30.5 mega-electron volts per meter. On-chip acceleration provides the possibility for a completely integrated mega-electron volt-scale DLA.

  View details for DOI 10.1126/science.aay5734

  View details for PubMedID 31896715

• Toward inverse-designed optical interconnect Skarda, J., Yang, K., Ahn, G., Guidry, M. A., Vuckovic, J., IEEE IEEE. 2020

  View details for Web of Science ID 000612237500103

• Inverse design of microresonator dispersion for nonlinear optics Ahn, G., Yang, K., Skarda, J., Vuclovic, J., IEEE IEEE. 2020

  View details for Web of Science ID 000612090001279

• Optical Parametric Oscillation Using 4H-SiC-on-Insulator Nanophotonics Guidry, M. A., Yang, K., Lukin, D. M., Yang, J., Vuckovic, J., IEEE IEEE. 2020

  View details for Web of Science ID 000612090003273

• 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

  View details for Web of Science ID 000612090002022

• 4H-silicon-carbide-on-insulator for integrated quantum and nonlinear photonics NATURE PHOTONICS Lukin, D. M., Dory, C., Guidry, M. A., Yang, K., Mishra, S. D., Trivedi, R., Radulaski, M., Sun, S., Vercruysse, D., Ahn, G., Vuckovic, J. 2020; 14: 330-334

  View details for DOI 10.1038/s41566-019-0556-6

• Architecture for the photonic integration of an optical atomic clock OPTICA Newman, Z. L., Maurice, V., Drake, T., Stone, J. R., Briles, T. C., Spencer, D. T., Fredrick, C., Li, Q., Westly, D., Ilic, B. R., Shen, B., Suh, M., Yang, K., Johnson, C., Johnson, D. S., Hollberg, L., Vahala, K. J., Srinivasan, K., Diddams, S. A., Kitching, J., Papp, S. B., Hummon, M. T. 2019; 6 (5): 680–85

  View details for DOI 10.1364/OPTICA.6.000680

  View details for Web of Science ID 000468373300021

• Inverse Design and Demonstration of Broadband Grating Couplers IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS Sapra, N. V., Vercruysse, D., Su, L., Yang, K., Skarda, J., Piggott, A. Y., Vuckovic, J. 2019; 25 (3)

  View details for DOI 10.1109/JSTQE.2019.2891402

  View details for Web of Science ID 000456927400001

• Vernier spectrometer using counterpropagating soliton microcombs SCIENCE Yang, Q., Shen, B., Wang, H., Minh Tran, Zhang, Z., Yang, K., Wu, L., Bao, C., Bowers, J., Yariv, A., Vahala, K. 2019; 363 (6430): 965-+

  View details for DOI 10.1126/science.aaw2317

  View details for Web of Science ID 000460194200042

• Vernier spectrometer using counterpropagating soliton microcombs. Science (New York, N.Y.) Yang, Q., Shen, B., Wang, H., Tran, M., Zhang, Z., Yang, K. Y., Wu, L., Bao, C., Bowers, J., Yariv, A., Vahala, K. 2019

  Abstract

  Determination of laser frequency with high resolution under continuous and abrupt tuning conditions is important for sensing, spectroscopy, and communications. We show that a single microresonator provides rapid and broadband measurement of optical frequencies with a relative frequency precision comparable to that of conventional dual-frequency comb systems. Dual-locked counterpropagating solitons having slightly different repetition rates were used to implement a vernier spectrometer, which enabled characterization of laser tuning rates as high as 10 terahertz per second, broadly step-tuned lasers, multiline laser spectra, and molecular absorption lines. Besides providing a considerable technical simplification through the dual-locked solitons and enhanced capability for measurement of arbitrarily tuned sources, our results reveal possibilities for chip-scale spectrometers that exceed the performance of tabletop grating and interferometer-based devices.

  View details for PubMedID 30792361

• Inverse-designed diamond photonics. Nature communications Dory, C. n., Vercruysse, D. n., Yang, K. Y., Sapra, N. V., Rugar, A. E., Sun, S. n., Lukin, D. M., Piggott, A. Y., Zhang, J. L., Radulaski, M. n., Lagoudakis, K. G., Su, L. n., Vučković, J. n. 2019; 10 (1): 3309

  Abstract

  Diamond hosts optically active color centers with great promise in quantum computation, networking, and sensing. Realization of such applications is contingent upon the integration of color centers into photonic circuits. However, current diamond quantum optics experiments are restricted to single devices and few quantum emitters because fabrication constraints limit device functionalities, thus precluding color center integrated photonic circuits. In this work, we utilize inverse design methods to overcome constraints of cutting-edge diamond nanofabrication methods and fabricate compact and robust diamond devices with unique specifications. Our design method leverages advanced optimization techniques to search the full parameter space for fabricable device designs. We experimentally demonstrate inverse-designed photonic free-space interfaces as well as their scalable integration with two vastly different devices: classical photonic crystal cavities and inverse-designed waveguide-splitters. The multi-device integration capability and performance of our inverse-designed diamond platform represents a critical advancement toward integrated diamond quantum optical circuits.

  View details for DOI 10.1038/s41467-019-11343-1

  View details for PubMedID 31346175

• Inverse Designed Diamond Nanophotonics Dory, C., Vercruysse, D., Yang, K., Sapra, N. V., Rugar, A. E., Sun, S., Lukin, D. M., Piggott, A. Y., Zhang, J. L., Radulaski, M., Lagoudakis, K. G., Su, L., Vuckovic, J., IEEE IEEE. 2019

  View details for Web of Science ID 000482226301122

• Inverse Designed Cavity-Waveguide Couplers Skarda, J., Yang, K., Vercruysse, D., Sapra, N. V., Su, L., Vuckovic, J., IEEE IEEE. 2019

  View details for Web of Science ID 000482226302359

• Waveguide-integrated dielectric laser particle accelerators through the inverse design of photonics Sapra, N. V., Yang, K., Vercruysse, D. F., Su, L., Vuckovic, J., IEEE IEEE. 2019

  View details for Web of Science ID 000482226302396

• Inverse designed Fano resonance in Silicon microresonators Yang, K., Skarda, J., Cotrufo, M., Ahn, G., Alu, A., Vuckovic, J., IEEE IEEE. 2019

  View details for Web of Science ID 000482226303042

• From Inverse Design to Implementation of Practical Photonics Skarda, J., Su, L., Yang, K., Vercruysse, D., Sapra, N. V., Vuckovic, J., IEEE IEEE. 2019

  View details for Web of Science ID 000524676400122