- Prof. W. Yao and Prof. X.D. Cui’s paper titled ‘Valley polarization in MoS_{2} monolayers by optical pumping’ was highlighted in Ars Technica.
Highlight in Ars Technica
Atomic and Quantum Physics Group
I. Quantum Computing and Information Theory
People
Academic staff |
Research staff |
Students |
Prof. Hoi Fung CHAU Prof. Zidan WANG |
Mr. Tao CHEN Dr. Zhen ZHENG |
Mr. Ming Lai CHAN (MPhil) Mr. Long Hin LI (PhD) Mr. Kwok Chung Joseph NG (MPhil) |
Research Activities
We focus on the theoretical study of quantum information theory and quantum computation. Our aim is to prove the security of various quantum cryptographic protocols as well as getting a better understanding of how to manipulate quantum information by quantum error-correction codes. In collaboration with researchers in HP Labs, Bristol, our group has recently proven that certain quantum key distribution scheme is unconditionally secure as well as obtained a U.S. patent on certain quantum key distribution protocols.
II. Theoretical Atomic Physics and Degenerate Quantum Gases
People
Academic staff |
Research staff |
Students |
Dr. Shizhong ZHANG |
Dr. Shanshan DING |
Mr. Ruibin LIU (PhD) |
Research Activities
Ultra-cold atomic gases have emerged as a multi-disciplinary subject that is at the interface of modern atomic and molecular physics, quantum optics and condensed matter physics. It proves to be an excellent laboratory for investigating strongly interacting quantum many-body systems and in particular correlated quantum phases and phase transitions. Current topics of interest include strongly interacting two-component Fermi gases and BEC-BCS crossover, synthetic gauge fields and spin-orbit couplings in atomic gases, novel mixtures of bosons and fermions.
Some Representative Publications
Prof. H.F. Chau
- "Decoy-State Quantum Key Distribution With More Than Three Types Of Photon Intensity Pulses", H. F. Chau, Physical Review A (Rapid Communications), 97, 040301(R) (2018).
- "Quantum Key Distribution Using Qudits That Each Encode One Bit Of Raw Key", H.F. Chau, Physical Review A, 92, 062324 (2015).
- "Metrics on Unitary Matrices and their Application to Quantifying the Degree of Non-commutativity between Unitary Matrices", H.F. Chau, Quantum Information and Computation, 11, 721-740 (2011).
- "Unconditionally Secure Key Distribution in Higher Dimensions by Depolarization", H.F. Chau, IEEE Transactions on Information Theory, 51, 1451-1468 (2005).
- "Practical scheme to share a secret key through a quantum channel with a 27.6% Bit Error Rate", H. F. Chau, Physical Review A, 66, 060302(R): 1-4 (2002).
- "Unconditional Security of Quantum Key Distribution over Arbitrarily Long Distances", H.K. Lo and H.F. Chau, Science, 283, 2050-2056 (1999).
- "Is Quantum Bit Commitment Really Possible?", H.K. Lo and H.F. Chau, Physical Review Letters, 78, 3410-3413 (1997).
Prof. Z.D. Wang
- "Novel Z_{2} topological metals and semimetals", Y. X. Zhao and Z. D. Wang, Phys. Rev. Lett. 116, 016401 (2016).
- "Unified theory of PT and CP invariant topological metals and nodal superconductors", Y. X. Zhao, A. P. Schynder, and Z. D. Wang, Phys. Rev. Lett. 116, 156402 (2016).
- "Disordered Weyl semimetals and their topological family", Y.X. Zhao and Z.D. Wang, Phys. Rev. Lett., 114, 206602 (2015).
- "Topological classification and stability of Fermi surfaces", Y.X. Zhao and Z.D. Wang, Phys. Rev. Lett., 110, 240404 (2013).
- "Unconventional Geometric Quantum Computation", S.L. Zhu and Z.D. Wang, Phys. Rev. Lett., 91, 187902 (2003).
- "Implementation of Universal Quantum Gates Based on Nonadiabatic Geometric Phases", S.L. Zhu and Z.D. Wang, Phys. Rev. Lett., 89, 097902 (2002).
Dr. S.Z. Zhang
- "Evidence for Universal Relations Describing a Gas with p-Wave Interactions", C. Luciuk, S. Trotzky, S. Smale, Z. Yu, S. Zhang, and J. H. Thywissen, Nature Physics, 6, 599-605 (2016)
- "Universal Relations for a Fermi Gas Close to a p-Wave Interaction Resonance", Z.H. Yu, J.H. Thywissen, S.Z. Zhang, Physical Review Letters, 115, 135304:1-5 (2015)
- “Transverse Demagnetization Dynamics of a Unitary Fermi Gas”, A.B. Bardon, S. Beattie, C. Luciuk, W. Cairncross, D. Fine, N.S. Cheng, G.J.A. Edge, E. Taylor, S.Z. Zhang, S. Trotzky, J.H. Thywissen, Science, 344, 722-724 (2014)
- “Theory of quantum oscillations in the vortex-liquid state of high-T_{c} superconductors”,S. Banerjee, S.Z. Zhang, M. Randeria, Nature Communications, 4, 1700:1-7 (2013)
- "Bose-Einstein condensates with spin-orbit interaction", T.L. Ho and S.Z. Zhang, Physics Review Letter, 107, 150403 (2011)
- "BEC-BCS crossover induced by a synthetic non-abelian gauge field", J.P. Vyasanakere, S.Z. Zhang and V. Shenoy, Physics Review B, 84, 014512 (2011)
- "Atom loss maximum in ultracold Fermi gases", S.Z. Zhang and T.L. Ho, New Journal of Physics, 13, 055003 (2011)
- "Universal properties of the ultracold Fermi gas", S.Z. Zhang and A.J. Leggett, Physics Review A, 79, 023601 (2009)