2016西北工大学术讲座：Topological insulators and superconductors

一、报告题目

       Topological insulators and superconductors

二、报告人

       Yew San Hor

三、讲座时间

       2016年11月15日下午2：00

四、讲座地点

       理学院学术报告厅

五、邀请人

       曹崇德教授

六、承办学院

       理学院

七、联系人

       曹崇德

       联系电话：15991732963

八、报告简介

       A novel kind of three-dimensional insulators called topological insulators, which have a bulk insulating gap but non-trivial topological surface states has been discovered. The surface states of these topological insulators show Dirac-like behavior with the spin polarization locked perpendicular to the electron momentum by the effect of strong spin-orbit interaction and protected by time-reversal symmetry. As the locking protects the surface electrons from back scattering, they are predicted to have high mobilities. The spin-resolved nature of the surface states has been confirmed in angle-resolved photoemission spectroscopy experiments. However, it has been a challenge to resolve the lack of transport information due to the dominant bulk conductance in the material. By chemical doping, the chemical potential of the material can be tuned to fall inside the band gap and therefore suppress the bulk conductivity. On the other hand, a topological insulator can also be tuned to a bulk superconductor. This means that Cooper pairing is possible in a topological insulator with implications for study of Majorana fermion physics and hence potential quantum computing devices. Moreover, detection of the surface currents is a crucial first step in the investigation of novel phenomena.

九、报告人简介

       Yew San Hor主要从事新颖的具有重大科学价值和未来应用前景的固态块体与纳米结构材料的研究与开发，尤其是拓扑绝缘体、拓扑超导体、关联体系和热电能源和制冷材料的探索。已在Science (3篇)、Nature (5篇)、Nature Physics (4篇)、Nautre Communications (1篇)、Physical Review Letters等国际顶级学术期刊发表学术论文60余篇，被他人引用超过7500次。