Debbie Leung

I study the capacity of communicating various form of data (quantum, private, or classical) through quantum channels, focusing on the superadditivity phenomenon. I also study how quantum entanglement, in particular, embezzlement of entanglement, plays a role in quantum information theory.
  • Tolman Postdoctoral Fellow, Theoretical Physics Institute for Quantum Information, Caltech, 2002-2005
  • Postdoctoral Fellow, Quantum Computation Mathematical Sciences Research Institute, Berkeley, 2002
  • Postdoctoral Fellow, Information group IBM T.J. Watson Research Center, 2000-2002
  • NSERC QUORUM project, Natural Sciences and Engineering Research Council of Canada, 2023
  • Discovery Grant, Natural Sciences and Engineering Research Council of Canada (NSERC), 2016-2023
  • Childs, A. M., Fu, H., Leung, D., Li, Z., Ozols, M., & Vyas, V. (2023). Streaming quantum state purification. arxiv:2309.16387v1
  • Khanian, Z. B., Kuroiwa, K., & Leung, D. (2023). Rate-Distortion Theory for Mixed States. In 2023 IEEE International Symposium on Information Theory (ISIT) Vol. 00 (pp. 749-754). Institute of Electrical and Electronics Engineers (IEEE). doi:10.1109/isit54713.2023.10206960
  • Leditzky, F., Leung, D., Siddhu, V., Smith, G., & Smolin, J. A. (2023). The Platypus of the Quantum Channel Zoo. IEEE Transactions on Information Theory, 69(6), 3825-3849. doi:10.1109/tit.2023.3245985
  • Leditzky, F., Leung, D., Siddhu, V., Smith, G., & Smolin, J. A. (2023). Generic Nonadditivity of Quantum Capacity in Simple Channels. Physical Review Letters, 130(20), 200801. doi:10.1103/physrevlett.130.200801
  • Kuroiwa, K., & Leung, D. (2023). Rate reduction of blind quantum data compression with local approximations based on the unstable structure of quantum states. Physical Review A, 107(5), 052421. doi:10.1103/physreva.107.052421
  • Girard, M., Leung, D., Levick, J., Li, C. -K., Paulsen, V., Poon, Y. T., & Watrous, J. (2022). On the Mixed-Unitary Rank of Quantum Channels. Communications in Mathematical Physics, 394(2), 919-951. doi:10.1007/s00220-022-04412-y
  • Khanian, Z. B., Kuroiwa, K., & Leung, D. (2022). Rate-Distortion Theory for Mixed States. doi:10.48550/arxiv.2208.11698
  • Tansuwannont, T., & Leung, D. (2022). Achieving Fault Tolerance on Capped Color Codes with Few Ancillas. PRX Quantum, 3(3), 030322. doi:10.1103/prxquantum.3.030322
  • Leditzky, F., Leung, D., Siddhu, V., Smith, G., & Smolin, J. A. (2022). The platypus of the quantum channel zoo. In 2022 IEEE International Symposium on Information Theory (ISIT) Vol. 00 (pp. 2433-2438). Institute of Electrical and Electronics Engineers (IEEE). doi:10.1109/isit50566.2022.9834678
  • Anshu, A., Leung, D., & Touchette, D. (2022). Incompressibility of Classical Distributions. IEEE Transactions on Information Theory, 68(3), 1758-1771. doi:10.1109/tit.2021.3130131
  • Tansuwannont, T., & Leung, D. (2021). Fault-tolerant quantum error correction using error weight parities. Physical Review A, 104(4), 042410. doi:10.1103/physreva.104.042410
  • Leung, D., Nayak, A., Shayeghi, A., Touchette, D., Yao, P., & Yu, N. (2021). Capacity Approaching Coding for Low Noise Interactive Quantum Communication Part I: Large Alphabets. IEEE Transactions on Information Theory, 67(8), 5443-5490. doi:10.1109/tit.2021.3086221
  • Leung, D., Winter, A., & Yu, N. (2021). LOCC protocols with bounded width per round optimize convex functions. Reviews in Mathematical Physics, 33(05), 2150013. doi:10.1142/s0129055x21500136
  • Rate-Distortion Theory for Mixed States, Analytical and Combinatorial Methods in Quantum Information Theory II, International Centre for Mathematical Sciences, Edinburgh, United Kingdom, 2023/07/28
  • Rate distortion theory for mixed state quantum data compression, CMS meeting, University of Ottawa, 2023/06/03
  • Quantum channel capacities and the platypus of the quantum channel zoo, Quantum Days 2023, Quantum Information Theory session, 2023/01/18
  • The platypus of the quantum channel zoo and their generic nonadditivity, CMS 2022 Winter Meeting, Toronto, 2022/12/04
  • Quantum channel capacities, 1st International Symposium on Trans-Scale Quantum Science (TSQS2021), University of Tokyo, Japan (online), 2021/10/29
  • The platypus of the quantum channel zoo, Oberwolfach workshop 2140b - Geometry and Optimization in Quantum Information, Oberwolfach Research Institute for Mathematics, Germany (hybrid), 2021/10/09
  • Additive quantities cannot be more than asymptotically continuous, Division of Theoretical Physics, Quantum Information Theory Session, Virtual Canadian Association of Physicists Congress 2021, 2021/06/08
  • Capacity approaching codes for interactive quantum communication in the low noise regime, 5th Quantum Software Consortium General Assembly 2021, Track Quantum networks, Networks conference 2021, Amsterdam, Netherlands, 2021/06/03
  • The embezzlement of entanglement and its applications, Quantum Software and Optimisation online workshop, Wallenberg Centre for Quantum Technology, Chalmers University of Technology in Gothenburg, Sweden, 2021/04/09