标题： 关联电子体系中的拓扑超导性
报告人： 王强华 教授
时间： 11月8日（周五）上午10点
地点： 田家炳楼南203室
邀请人： 董帅

Abstract: In this talk we first provide a brief introduction to the topological states of matter. Topoloigcal superconductor is understood to be an analogue of topological insulators. While conceptually simple, the search of topological superconductor relies on careful treatment of the interactions at multiple energy scales. For this purpose we introduce the idea of functional renormalization group. Equipped with this method, we study/predict topological superconductivity in correlated systems. Specifically, we show that 1) A chial d+id'-wave pairing can be realized in doped graphene and kagome model near the van Hove level, 2) A chiral p+ip'-wave pairing is realized in Sr2RuO4, with dominant pairing in the gamma-band. The gap function has deep gap minima. This resolves some, if not all, of the long-standing issues in this system. 3) We provide concrete models that can support time-reversal invariant topological pairing, thus providing a roadmap for the search of such superconductors. 4) Finally we address the superconductivity in the new BiS2 superconductors. We find that the leading pairing channel is time-reversal invariant and is dominated by triplet components. More interestingly in the low doping regime the pairing is weak topological. We end with remarks on the mechanism toward topological superconductivity.

报告人简介：南京大学物理学经理江学者特聘教授，国家杰出青年基金获得者。研究领域为高温超导体及有关强关联电子系统的理论研究, 新超导材料的超导机理和物理性质的理论研究，拓扑绝缘体与拓扑超导体的理论研究，量子信息与量子计算的理论研究。