- Research
- Introduction
- Facilities
- Research Groups
- Area of Excellence Project
- Astronomy and Astrophysics
- Centre of Theoretical & Computational Physics
- Experimental Condensed Matter Physics Group
- Experimental High Energy Particle Physics Group
- Experimental Nuclear Physics Group
- Material Science Group
- Quantum Computing and Information Theory
- Theoretical Atomic Physics and Degenerate Quantum Gases
- Theoretical Condensed Matter Physics Group
- Publications
- 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
Theoretical Condensed Matter Physics Group
Valley-spintronics in atomically thin 2D semiconductors |
People
Academic staff |
Research staff |
Students |
Prof. Shunqing SHEN Prof. Jian WANG Dr. Yin WANG Prof. Zidan WANG Prof. Wang YAO Dr. Lei ZHANG Dr. Shizhong ZHANG Dr. Yuxin ZHAO |
Dr. Xiaobin CHEN |
Mr. King Tai CHEUNG (PhD) |
Research Activities
Theoretical condensed matter physics is a very important area in physical sciences because not only it concerns with many fundamental subjects but also it has very wide and potentially important applications in material science, biophysical science, high technology, and even economy and finance, etc. We have a very active research group in this field. Our current research interest includes:
- strongly correlated electron systems;
- topological quantum materials;
- quantum computing;
- quantum magnetism;
- spintronics and valleytronics;
- quantum transport;
- semiconductor optics;
- interdisciplinary study of cold atom physics and condensed matter physics
Optical properties, including nonlinear optical properties, electronic structures, electron-phonon interactions, and ultrafast phenomena, in semiconductor nanostructures (e.g., quantum wells, dots and nanocrystals). The laboratory is equipped with variable-temperature (4.2K-300K) photoluminescence system, confocal micro-Raman system combined with a 77K-500K variable-temperature cooler, variable-temperature (10K-330K) broadband (200nm-1700nm) emission/absorption spectroscopy, ultrafast (sub-ps) time-resolved photoluminescence, and the near-field scanning optical microscopy.
(1) Prof. J. Wang: During the past ten years, our research evolves around the development of first principle quantum transport formalism as well as its practical implementation in nanoelectronics. On formalism developments, we have formulated a current conserving and gauge invariant theoretical framework based on the Keldysh non-equilibrium Green's functions to predict finite frequency AC as well as nonlinear DC quantum transport properties. In addition, we have combined the quantum transport theory and the density function theory and developed a start of the art first principle quantum transport theory (NEGF+DFT), calculation method, and computer code. Our method is the de facto standard technique for modeling quantum transport including all atomic, material and chemical details of the device.
(2) Prof. S.Q. Shen, an expert in the field of condensed matter physics, is distinguished for his research works on spintronics of semiconductors, quantum magnetism and orbital physics in transition metal oxides, and novel quantum states of condensed matters. He proposed theory of topological Anderson insulator, spin transverse force, resonant spin Hall effect and theory of phase separation in colossal magnetoresistive (CMR) materials. He proved existence of antiferromagnetic long-range order and off-diagonal long-range order in itinerant electron systems.
(3) Dr. W. Yao: We are a theoretical group working in an interdisciplinary field across condensed matter physics, quantum physics, and optical physics. Our research interests cover open quantum systems and quantum environment, quantum controls, cavity quantum electrodynamics, semiconductor optics, and topological quantum transport.
Some Representative Publications
Prof. S.Q. Shen
- "Negative magnetoresistance in Dirac semimetal Cd_{3}As_{2}", H. Li, H. He, H.Z. Lu, H. Zhang, H. Liu, R. Ma, Z. Fan, S.Q. Shen, and J. Wang, Nature Communications, 7, 10301 (2016)
- "Topological superconducting states in monolayer FeSe/SrTiO_{3}", N.N. Hao and S.Q. Shen, Physical Review B, 92, 165104 (2015)
- "Weak antilocalization and localization in disordered and interacting Weyl semimetals", Hai-Z. Lu and S.Q. Shen, Physical Review B, 92, 035203 (2015)
- "Finite temperature conductivity and magnetoconductivity of topological insulators" H.Z. Lu and S.Q. Shen, Physical Review Letters, 112, 146601 (2014)
- "Quantum transport in magnetic topological insulator thin film", H.Z. Lu, A. Zhao and S.Q. Shen, Physical Review Letters, 111, 146802 (2013)
- "Intervalley scattering and localization behaviors of spin-valley coupled Dirac fermions", H.Z. Lu, A. Zhao and S.Q. Shen, Physical Review Letters, 111, 146802 (2013)
- "Competition between Weak Localization and Antilocalization in Topological Surface States", H.Z. Lu, W. Yao, D. Xiao, and S.Q. Shen, Physical Review Letters, 107, 076801 (2011)
- "Topological Anderson Insulator", J. Li, R.L. Chu, J.K. Jain and S.Q. Shen, Physical Review Letters, 102, 136806 (2009).
Prof. J. Wang
- "Controllable Andreev Retroreflection and specular Andreev reflection in a four-terminal Graphene-Superconductor hybrid system", S.G. Cheng, Y.X. Xing, J. Wang, and Q.F. Sun, Phys. Rev. Lett., 103, 167003 (2009).
- "Universal quantized spin-Hall conductance fluctuation in graphene", Z.H. Qiao, J. Wang, Y.D. Wei, and H. Guo, Phys. Rev. Lett., 101, 016804 (2008).
- "Persistent spin current in a mesoscopic hybrid ring with spin-orbit coupling", Q.F. Sun, X.C. Xie, and J. Wang, Phys. Rev. Lett., 98, 196801 (2007).
- "Low-field phase diagram of the spin Hall effect in the mesoscopic regime", Z.H. Qiao, W. Ren, J. Wang, and H. Guo, Phys. Rev. Lett., 98, 196402 (2007).
- "Universal spin-Hall conductance fluctuations in two dimensions", W. Ren, Z.H. Qiao, J. Wang, Q.F. Sun, and H. Guo, Phys. Rev. Lett., 97, 066603 (2006).
- "ab initio modeling of quantum transport properties of molecular electronic devices", J. Taylor, H. Guo, and J. Wang, Phys. Rev. B, 63, 245407 (2001).
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. W. Yao
- “Excitonic luminescence upconversion in a two-dimensional semiconductor”, A. Jones, Hongyi Yu, J. Schaibley, J. Yan, D. Mandrus, T. Taniguchi, K. Watanabe, H. Dery, W. Yao and X. Xu, Nature Physics, 12, 323 (2016)
- "Anomalous light cones and valley optical selection rules of interlayer excitons in twisted heterobilayers", Hongyi Yu, Y. Wang, Qingjun Tong, X. Xu and Wang Yao, Phys. Rev. Lett., 115, 187002 (2015)
- “Magnetic control of valley pseudospin in monolayer WSe_{2}”, G. Aivazian, Z.R. Gong, A. Jones, R. Chu, J. Yan, D. Mandrus, C. Zhang, D. Cobden, W. Yao and X. Xu, Nature Physics, 11, 148 (2015)
- “Electronic structures and theoretical modelling of two-dimensional group-VIB transition metal dichalcogenides”, G.B. Liu, D. Xiao, Y.G. Yao, X.D. Xu and W. Yao, Chem. Soc. Rev., 44, 2643 (2015)
- “Nonlinear valley and spin currents from Fermi pocket anisotropy in 2D crystals”, H.Y. Yu, Y. Wu, G.B. Liu, X.D. Xu and W. Yao, Phys. Rev. Lett. 113, 156603 (2014)
- “Dirac cones and Dirac saddle points of bright excitons in monolayer transition metal dichalcogenides”, H.Y. Yu, G.B. Liu, P. Gong, X.D. Xu and W. Yao, Nature Communications, 5, 3876 (2014)
- Spins and pseudospins in layered transition metal dichalcogenides, X. Xu, W. Yao, D. Xiao and T. F. Heinz, Nature Physics, 10, 343 (2014)
- "Optical generation of excitonic valley coherence in monolayer WSe_{2}", A. Jones, H.Y. Yu, N. Ghimire, S.F. Wu, G. Aivazian, J. Ross, B. Zhao, J.Q. Yan, D. Mandrus, D. Xiao, W. Yao, X.D. Xu, Nature Nanotechnology, 8, 634 (2013)
- "Magnetoelectric effects and valley controlled spin quantum gates in transition metal dichalcogenide bilayers", Z.R. Gong, G.B. Liu, H.Y. Yu, D. Xiao, X.D. Cui, X.D. Xu, W. Yao, Nature Communications, 4, 2053 (2013)
- "Coupled Spin and Valley Physics in Monolayers of MoS_{2} and Other Group-VI Dichalcogenides", D. Xiao, G.B. Liu, W.X. Feng, X.D. Xu and W. Yao, Physical Review Letters, 108, 196802 (2012)
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)