【理学院专题学术讲座】

主讲人：何宇驰博士，牛津大学

主题：Symmetry-breaking and topological quantum phases in twisted bilayer transition metal dichalcogenide

时间：2024年1月11日（周四）下午2:00-3:30

地点： 我院云谷校区E10-211

主持人：澳门沙金游戏app理学院吴从军讲席教授

主讲人：

何宇驰博士，牛津大学

主讲人简介/Biography:

Dr. Yuchi He obtained his PhD in the physics department of Carnegie Mellon University, USA in 2020. Before that, he got his BS in Peking University. He worked as a postdoc in RWTH Aachen University and now work in the University of Oxford. His primary research interest is phases and dynamics of strongly correlated quantum many-body systems. One-dimensional and two-dimensional systems are investigated by application and development of effective field theory and tensor networks. Most recently, he is interested in twisted transition metal dichalcogenides and driven-dissipative systems.

讲座摘要/Abstract:

The investigation of twisted bilayer graphene has opened a “twistronics era”, providing unprecedented tunability for solid-state systems and an excellent platform for strongly correlated quantum phases and their transitions. While twisted bilayer graphene requires involved multi-band descriptions, twisted bilayer transition metal dichalcogenides are simpler. We theoretically study two cases of twisted bilayer transition metal dichalcogenides: (1) effective triangular systems and (2) effective honeycomb systems. For triangular systems, we study possible magnetic orders and spin liquids at half-filling; we also study the magnetic orders at the van Hove filling, providing an explanation for the absence of the predicted quantum anomalous Hall effect in experiments. For honeycomb systems, we numerically reveal integer and fractional quantum anomalous Hall effects, providing theoretical support for the ground-breaking experimental discovery of fractional quantum anomalous Hall effects.