Honors & Awards


  • Andreas Bechtolsheim Stanford Graduate Fellowship, Stanford University

Education & Certifications


  • M.Sc., Technical University of Munich, Condensed Matter Physics (2015)
  • B.Sc., Technical University of Munich, Physics (2013)

Stanford Advisors


Lab Affiliations


All Publications


  • Cavity-Enhanced Raman Emission from a Single Color Center in a Solid. Physical review letters Sun, S., Zhang, J. L., Fischer, K. A., Burek, M. J., Dory, C., Lagoudakis, K. G., Tzeng, Y., Radulaski, M., Kelaita, Y., Safavi-Naeini, A., Shen, Z., Melosh, N. A., Chu, S., Loncar, M., Vuckovic, J. 2018; 121 (8): 083601

    Abstract

    We demonstrate cavity-enhanced Raman emission from a single atomic defect in a solid. Our platform is a single silicon-vacancy center in diamond coupled with a monolithic diamond photonic crystal cavity. The cavity enables an unprecedented frequency tuning range of the Raman emission (100GHz) that significantly exceeds the spectral inhomogeneity of silicon-vacancy centers in diamond nanostructures. We also show that the cavity selectively suppresses the phonon-induced spontaneous emission that degrades the efficiency of Raman photon generation. Our results pave the way towards photon-mediated many-body interactions between solid-state quantum emitters in a nanophotonic platform.

    View details for DOI 10.1103/PhysRevLett.121.083601

    View details for PubMedID 30192607

  • Strongly Cavity-Enhanced Spontaneous Emission from Silicon-Vacancy Centers in Diamond NANO LETTERS Zhang, J., Sun, S., Burek, M. J., Dory, C., Tzeng, Y., Fischer, K. A., Kelaita, Y., Lardakis, K. G., Radulaski, M., Shen, Z., Melosh, N. A., Chu, S., Loncar, M., Vuckovic, J. 2018; 18 (2): 1360–65

    Abstract

    Quantum emitters are an integral component for a broad range of quantum technologies, including quantum communication, quantum repeaters, and linear optical quantum computation. Solid-state color centers are promising candidates for scalable quantum optics due to their long coherence time and small inhomogeneous broadening. However, once excited, color centers often decay through phonon-assisted processes, limiting the efficiency of single-photon generation and photon-mediated entanglement generation. Herein, we demonstrate strong enhancement of spontaneous emission rate of a single silicon-vacancy center in diamond embedded within a monolithic optical cavity, reaching a regime in which the excited-state lifetime is dominated by spontaneous emission into the cavity mode. We observe 10-fold lifetime reduction and 42-fold enhancement in emission intensity when the cavity is tuned into resonance with the optical transition of a single silicon-vacancy center, corresponding to 90% of the excited-state energy decay occurring through spontaneous emission into the cavity mode. We also demonstrate the largest coupling strength (g/2π = 4.9 ± 0.3 GHz) and cooperativity (C = 1.4) to date for color-center-based cavity quantum electrodynamics systems, bringing the system closer to the strong coupling regime.

    View details for DOI 10.1021/acs.nanolett.7b05075

    View details for Web of Science ID 000425559700102

    View details for PubMedID 29377701

  • On-Chip Architecture for Self-Homodyned Nonclassical Light PHYSICAL REVIEW APPLIED Fischer, K. A., Kelaita, Y. A., Sapra, N. V., Dory, C., Lagoudakis, K. G., Mueller, K., Vuckovic, J. 2017; 7 (4)
  • On-Chip Architecture for Self-Homodyned Nonclassical Light PHYSICAL REVIEW APPLIED Fischer, K. A., Kelaita, Y. A., Sapra, N. V., Dory, C., Lagoudakis, K. G., Mueller, K., Vuckovic, J. 2017; 7 (4)
  • Tuning the photon statistics of a strongly coupled nanophotonic system PHYSICAL REVIEW A Dory, C., Fischer, K. A., Mueller, K., Lagoudakis, K. G., Sarmiento, T., Rundquist, A., Zhang, J. L., Kelaita, Y., Sapra, N. V., Vuckovic, J. 2017; 95 (2)
  • Observation of Mollow Triplets with Tunable Interactions in Double Lambda Systems of Individual Hole Spins PHYSICAL REVIEW LETTERS Lagoudakis, K. G., Fischer, K. A., Sarmiento, T., McMahon, P. L., Radulaski, M., Zhang, J. L., Kelaita, Y., Dory, C., Muller, K., Vuckovic, J. 2017; 118 (1)

    Abstract

    Although individual spins in quantum dots have been studied extensively as qubits, their investigation under strong resonant driving in the scope of accessing Mollow physics is still an open question. Here, we have grown high quality positively charged quantum dots embedded in a planar microcavity that enable enhanced light-matter interactions. Under a strong magnetic field in the Voigt configuration, individual positively charged quantum dots provide a double lambda level structure. Using a combination of above-band and resonant excitation, we observe the formation of Mollow triplets on all optical transitions. We find that when the strong resonant drive power is used to tune the Mollow-triplet lines through each other, we observe anticrossings. We also demonstrate that the interaction that gives rise to the anticrossings can be controlled in strength by tuning the polarization of the resonant laser drive. Quantum-optical modeling of our system fully captures the experimentally observed spectra and provides insight on the complicated level structure that results from the strong driving of the double lambda system.

    View details for DOI 10.1103/PhysRevLett.118.013602

    View details for Web of Science ID 000391474000011

    View details for PubMedID 28106434

  • Tuning the Photon Statistics of a Strongly Coupled Nanophotonic System PHYSICAL REVIEW A Dory, C., Fischer, K. A., Müller, K., Lagoudakis, K. G., Sarmiento, T., Rundquist, A., Zhang, J. L., Kelaita, Y., Sapra, N. V., Vuckovic, J. 2017; 95: 023804
  • Complete Coherent Control of Silicon-Vacancies in Diamond Nanopillars Containing Single Defect Centers Zhang, J., Lagoudakis, K. G., Tzeng, Y., Dory, C., Radulaski, M., Kelaita, Y., Fischer, K. A., Shen, Z., Melosh, N. A., Chu, S., Vuckovic, J., IEEE IEEE. 2017
  • Effects of Homodyne Interference on Jaynes-Cummings Emission for Single Photon Generation Fischer, K. A., Kelaita, Y. A., Sapra, N. V., Dory, C., Lagoudakis, K. G., Mueller, K., Vuckovic, J., IEEE IEEE. 2017
  • Tuning the Photon Statistics of a Strongly Coupled Nanophotonic System Dory, C., Fischer, K. A., Mueller, K., Lagoudakis, K. G., Sarmiento, T., Rundquist, A., Zhang, J. L., Kelaita, Y., Sapra, N. V., Vuckovic, J., IEEE IEEE. 2017
  • Ultrafast coherent manipulation of trions in site-controlled nanowire quantum dots OPTICA Lagoudakis, K. G., McMahon, P. L., Dory, C., Fischer, K. A., Mueller, K., Borish, V., Dalacu, D., Poole, P. J., Reimer, M. E., Zwiller, V., Yamamoto, Y., Vuckovic, J. 2016; 3 (12): 1430-1435
  • Self-homodyne-enabled generation of indistinguishable photons OPTICA Mueller, K., Fischer, K. A., Dory, C., Sarmiento, T., Lagoudakis, K. G., Rundquist, A., Kelaita, Y. A., Vuckovic, J. 2016; 3 (9): 931-936
  • Complete Coherent Control of a Quantum Dot Strongly Coupled to a Nanocavity SCIENTIFIC REPORTS Dory, C., Fischer, K. A., Mueller, K., Lagoudakis, K. G., Sarmiento, T., Rundquist, A., Zhang, J. L., Kelaita, Y., Vuckovic, J. 2016; 6

    Abstract

    Strongly coupled quantum dot-cavity systems provide a non-linear configuration of hybridized light-matter states with promising quantum-optical applications. Here, we investigate the coherent interaction between strong laser pulses and quantum dot-cavity polaritons. Resonant excitation of polaritonic states and their interaction with phonons allow us to observe coherent Rabi oscillations and Ramsey fringes. Furthermore, we demonstrate complete coherent control of a quantum dot-photonic crystal cavity based quantum-bit. By controlling the excitation power and phase in a two-pulse excitation scheme we achieve access to the full Bloch sphere. Quantum-optical simulations are in good agreement with our experiments and provide insight into the decoherence mechanisms.

    View details for DOI 10.1038/srep25172

    View details for Web of Science ID 000375066300001

    View details for PubMedCentralID PMC4845032

  • Self-homodyne measurement of a dynamic Mollow triplet in the solid state NATURE PHOTONICS Fischer, K. A., Mueller, K., Rundquist, A., Sarmiento, T., Piggott, A. Y., Kelaita, Y., Dory, C., Lagoudakis, K. G., Vuckovic, J. 2016; 10 (3): 163-?
  • Hybrid Group IV Nanophotonic Structures Incorporating Diamond Silicon-Vacancy Color Centers NANO LETTERS Zhang, J. L., Ishiwata, H., Babinec, T. M., Radulaski, M., Mueller, K., Lagoudakis, K. G., Dory, C., Dahl, J., Edgington, R., Souliere, V., Ferro, G., Fokin, A. A., Schreiner, P. R., Shen, Z., Melosh, N. A., Vuckovic, J. 2016; 16 (1): 212-217

    Abstract

    We demonstrate a new approach for engineering group IV semiconductor-based quantum photonic structures containing negatively charged silicon-vacancy (SiV(-)) color centers in diamond as quantum emitters. Hybrid diamond-SiC structures are realized by combining the growth of nano- and microdiamonds on silicon carbide (3C or 4H polytype) substrates, with the subsequent use of these diamond crystals as a hard mask for pattern transfer. SiV(-) color centers are incorporated in diamond during its synthesis from molecular diamond seeds (diamondoids), with no need for ion-implantation or annealing. We show that the same growth technique can be used to grow a diamond layer controllably doped with SiV(-) on top of a high purity bulk diamond, in which we subsequently fabricate nanopillar arrays containing high quality SiV(-) centers. Scanning confocal photoluminescence measurements reveal optically active SiV(-) lines both at room temperature and low temperature (5 K) from all fabricated structures, and, in particular, very narrow line widths and small inhomogeneous broadening of SiV(-) lines from all-diamond nanopillar arrays, which is a critical requirement for quantum computation. At low temperatures (5 K) we observe in these structures the signature typical of SiV(-) centers in bulk diamond, consistent with a double lambda. These results indicate that high quality color centers can be incorporated into nanophotonic structures synthetically with properties equivalent to those in bulk diamond, thereby opening opportunities for applications in classical and quantum information processing.

    View details for DOI 10.1021/acs.nanolett.5b03515

    View details for Web of Science ID 000368322700034

  • Complete Coherent Control of a Quantum Dot Strongly Coupled to a Nanocavity. Scientific reports Dory, C., Fischer, K. A., Müller, K., Lagoudakis, K. G., Sarmiento, T., Rundquist, A., Zhang, J. L., Kelaita, Y., Vuckovic, J. 2016; 6: 25172-?

    Abstract

    Strongly coupled quantum dot-cavity systems provide a non-linear configuration of hybridized light-matter states with promising quantum-optical applications. Here, we investigate the coherent interaction between strong laser pulses and quantum dot-cavity polaritons. Resonant excitation of polaritonic states and their interaction with phonons allow us to observe coherent Rabi oscillations and Ramsey fringes. Furthermore, we demonstrate complete coherent control of a quantum dot-photonic crystal cavity based quantum-bit. By controlling the excitation power and phase in a two-pulse excitation scheme we achieve access to the full Bloch sphere. Quantum-optical simulations are in good agreement with our experiments and provide insight into the decoherence mechanisms.

    View details for DOI 10.1038/srep25172

    View details for PubMedID 27112420

    View details for PubMedCentralID PMC4845032

  • Controlled tunneling-induced dephasing of Rabi rotations for high-fidelity hole spin initialization PHYSICAL REVIEW B Ardelt, P., Simmet, T., Mueller, K., Dory, C., Fischer, K. A., Bechtold, A., Kleinkauf, A., Riedl, H., Finley, J. J. 2015; 92 (11)
  • Ultrafast Polariton-Phonon Dynamics of Strongly Coupled Quantum Dot-Nanocavity Systems PHYSICAL REVIEW X Mueller, K., Fischer, K. A., Rundquist, A., Dory, C., Lagoudakis, K. G., Sarmiento, T., Kelaita, Y. A., Borish, V., Vuckovic, J. 2015; 5 (3)