Imaging electrons in 6 dimensions: new opportunities from spectromicroscopy on topological quantum materials
Prof. L. Andrew Wray
Department of Physics, New York University
时间：2020年11月25日（周三）上午11:00-12:00
方式：腾讯会议ID 351 969 969
Abstract
The technique of angle resolved photoemission spectroscopy (ARPES) is used to observe the 3+1 dimensional momentum and energy contours of electronic quasiparticles inside materials, and can reveal key properties such as effective mass and quantum topology. The last few years have seen the roll-out of a new generation of ARPES spectrographs that augment the technique with micron- and nanometer-scale spatial resolution. I will talk about the profound implications this upgrade has for our understanding of quantum materials, taking the example of recent measurements by my group on the topological insulator Bi2Se3, the topological Kondo insulator SmB6, and the topological superconductor UTe2. The addition of spatial resolution enables us to use the intrinsic inhomogeneity of samples as a 'natural doping series', providing a powerful new paradigm to observe interdependencies in electronic structure, such as the hallmarks of strong correlations and band hybridization.
报告人简介：L. Andrew Wray 现任纽约大学物理系助理教授。作。他于2010年在普林斯顿大学获得凝聚态物理博士学位。之后他参与负责伯克利国家实验室和斯坦福材料与能源科学研究所的科研工作，并在2014年他加入纽约大学。L. Andrew Wray教授的研究方向是利用先进的X射线谱学实验技术去发现，表征和操控拓扑量子材料(拓扑绝缘体，拓扑超导体)中的新奇量子态，以及研究对应X射线谱学技术的模拟方法。
About Prof. L. Andrew Wray:
L. Andrew Wray is an Assistant Professor of Physics at New York University. He holds a Ph.D. in Experimental Condensed Matter Physics from Princeton University (2010) and a B.A. in Physics from the University of California, Berkeley, and conducted pre-doctoral research at the Institute of Physics, Chinese Academy of Sciences. After completing his Ph.D., Wray led research projects at the Lawrence Berkeley National Laboratory (LBNL) and Stanford Institute for Materials and Energy Sciences (SIMES) prior to joining the NYU faculty in 2014. Wray’s research focuses on the discovery, characterization and manipulation of novel quantum states inside materials. His experiments have been instrumental in identifying the first realizations of topologically ordered quantum states of matter such as the topological insulator and topological superconductor. Incisive in-situ investigation of the energy and momentum profiles of quantum states is made possible by rapidly advancing capabilities at state of the art X-ray facilities. Wray maintains active involvement in proposing new X-ray science technologies and developing novel methods to simulate and analyze resonant interactions between X-rays and matter.