学术报告信息(2017年5月19日)

By: bgs, PostTime: 2017/5/12, Visits: 3208

报告题目:BEC in degenerate rings.
报告时间:5月19日(周五)上午10:00
报告地点:理6栋220
报告人:中国科技大学(USTC)  龚明 教授、青年千人 
报告摘要:
      Symmetries play an essential role in condensed matter physics. In this work we consider the Bose-Einstein condensation (BEC) in the presence of time-reversal symmetry and inversion symmetry in a bilayer system, in which the single particle minimal is determined by two degenerate rings. This extra degeneracy can fundamentally change the fate of BEC with interaction. Especially, we find that the plane wave phase can be formed even when the inter-particle interaction dominates due to the possible scattering in the degenerate space. Thus this extra degree of freedom can relax the spin-momentum locking effect. When the degenerate rings have different sizes, different stripe phases with two or four colinear momenta can be realized. The crossover between these two cases will be accompanied by the excited band condensation due to the interference effect, which can be realized even with moderate interaction strength.

报告人简介:
      龚明博士2010年毕业于中国科技大学,2010.10-2012.12在美国Washington State University 和 University of Texas at Dallas做博后,2012.12到香港中文大学物理系任研究助理教授。2015年至今为中国科技大学教授、博士生导师、青年千人计划入选者。他主要研究固体和费米气体中的拓扑性质,在国际顶级期刊Nature Communications, Physical Reviewer Letters等上发表了一系列学术论文。