20200927 卡耐基梅隆大学张银寒博士学术报告

By: 李聪鹏, PostTime: 2020/9/25, Visits: 74

报告题目:Symmetry and topology: a new perspective in low dimensional materials
报告人:张银寒博士  卡耐基梅隆大学
时间:2020/9/27  上午09:00 
腾讯会议 ID:944 574 816 
摘要: Berry phase and topology, as a new perspective, plays significant roles in understanding and predicting properties of low-dimensional materials. In this report, we first introduce some basic concepts about the Berry phase and topology, and a simple toy model. Second, we will investigate observable effects of the Berry curvature in various low-dimensional materials, including magnetic insulators, twisted bilayer system, and fractional quantum Hall system. In magnetic insulating state, we point out that the spin Nernst effect still survives even in the paramagnetic region of antiferromagnetic insulators. Further we explore the effect of the interaction of phonons and magnons on the Berry curvature, and find that the thermal Hall effect will appear only when tuning on the hybrid interaction. In addition, we propose an adiabatic transport can be achieved in the twisted bilayer system, and we also find a tunable photogalvanic phenomena can be hosted by the twisted bilayer materials. Finally, we propose a new exotic state: quantum anomalous Hall insulator of composite fermions in fractional quantum Hall regimes, and its corresponding density functional theory.

报告人简介:张银寒博士,自2010于中科院物理所攻读博士学位,在施均仁教授指导下研究分数量子霍尔效应以及相关课题,并于2014年获得博士学位。2014年到2016年期间在北京大学量子材料中心从事博士后研究工作。2016年至今在美国卡耐基梅隆大学物理系肖笛教授研究组担任博士后研究人员,并从事二维材料中的Berry相位和拓扑效应的研究,目前主要关注人工合成材料如twisted bilayer体系中的新奇物性(输运、光学、多体物理)、凝聚态体系中量子反常相关的物理效应。迄今在Phys Rev Lett、Phys Rev B等国际期刊发表论文近13篇。