报告人：杨理副教授（华盛顿大学圣路易斯分校）

时间：2017年10月28日(周六)下午2:00

Abstract:My talk will mainly cover two parts of our recent works. In the first part, I will introduce a powerful first-principles tool, the GW-Bethe Salpeter Equation (BSE) approach, which can accurately capture many-electron interactions and predict excited-state properties of solids. Particularly, the reduced dimensionality substantially reduces the screening and enhances many-electron interactions. As a result, many-electron effects dictate quasiparticle energies and optical response of two-dimensional (2D) materials. In the second part, I will present our studies of the unusual electronic, optical, and thermal properties of a new family of 2D materials, black phosphorus (BP). More recently, we find that group IV-VI materials, which are isoelectronic ones of BP, may exhibit dramatically enhanced piezoelectric effects. Interestingly, these monolayer group IV monochalcogenides are essentially spontaneously polarized and hold the robust ferroelectric effect above room temperature.

简历：Li Yang received his BS (1997) and MS (2000) from the Beijing Normal University and PhD from the Georgia Institute of Technology (2006). From 2006 to 2009, he had worked as a postdoctoral fellow at the University of California, Berkeley. In 2009, he joined the faculty of the physics department of the Washington University in St Louis. He has published 64 peer-reviewed articles with around 7,700 citations. He received the Faculty Early Career Development Award (CAREER) from the National Science Foundation (NSF) in 2015. Using first-principles simulations and models, his group are working on condensed matter physics and studying fundamental electronic structures, transport, polarization, and excited-state properties of reduced dimensional materials.

联系方式：物理学院办公室（68913163）

邀请人：刘贵斌副教授网址：http://www.nbhongshu.com/