| 报告题目 | Disorder Effects in Topological Systems |
| 报告人 | Prof. JIANG Hua |
| 报告人单位 | School of Physics, Soochow University |
| 报告时间 | 2014-05-14 |
| 报告地点 | 合肥微尺度物质科学国家实验室九楼会议室 |
| 主办单位 | 合肥微尺度物质科学国家实验室、国际功能材料量子设计中心、中国科学技术大学物理系 |
| 报告介绍 | 报告摘要：
Due to their fantastic electronic properties and promising applications, Z2=1 topological insulators have generated considerable attentions. In this talk, we study the disorder effects in various Z2=0 topological systems. In Z2=0 HgTe/CdTe quantum wells and Graphene with adatom systems, we find the random Anderson disorder (or adatom distribution) leads to a novel quantum transition: from a Z2=0 trivial insulator to a Z2=1 topological insulator. In general, the edge states in Z2=0 systems are considered to be fragile in the presence of disorder. However, recently, we predict the emergence of robust helical edge states in both 2D and 3D systems, arising from finite size confinement. Based on the transport simulation, we demonstrate that the surface states is robust against nonmagnetic disorder. These emerging robust helical states lead to the revival of major features of Z2=1 systems. Notably, the effective energy gap of the robust helical states can be efficiently engineered, allowing for potential applications as valley filters and valley valves. The prediction has been verified by the experiment.
报告人简介：
Hua Jiang received his B.S. degree from Nanjing University in 2005 and Ph.D degree from Institute of Physics, Chinese Academy of Science in 2010. Then he worked as a postdoctoral fellow at International Center for Quantum Materials, Peking University. In 2013, he joined the School of Physics, Soochow University as a faculty number and works in the field of Condensed Matter Theory. His research interests are engineering topological phases and studying their related quantum transport phenomena in low dimensional systems. |
