International Center for Quantum Materials, Peking University

报告人简介：

刘雄军教授2011年博士毕业于德州A&M大学物理系。2011年至2014年分别在马里兰大学凝聚态物理中心和联合量子研究所，香港科大高等研究院以及麻省理工学院物理系从事博士后研究。他于2014年9月加入北京大学量子材料科学中心任研究员，博士生导师。2018年7月获得终身长聘职位，同年8月获得国家杰青资助。刘雄军教授长期在拓扑物相和超冷原子量子模拟领域开展研究。他在人工规范场量子模拟，拓扑超导领域做出一系列原创工作；尤其在推动近些年人工自旋轨道耦合量子模拟方向的理论和实验发展有重要贡献。目前发表50余篇论文，主要以通讯作者或一作发表在Science，Science子刊，Nature子刊，PRX，PRL等期刊上。他目前的主要研究兴趣集中在拓扑超导，人工规范场量子模拟，非平衡拓扑量子系统，强关联拓扑物相等方面。

报告摘要：

Topological phase of matter is a main stream of research in condensed matter physics. In this talk I introduce how to characterize topological phases by non-equilibrium quantum dynamics, and show its application to detecting topological physics with high precision. The framework of the theory consists of basic findings. First, we show that classifying a generic d-dimensional (dD) gapped topological phase with integer invariants can reduce to a (d-1)D invariant defined on so-called band inversion surfaces (BISs), rendering a bulk-surface duality. Further, we show in quenching across phase boundary the (pseudo)spin dynamics to exhibit emergent topological patterns on BISs, which are attributed to the post-quench bulk topology and manifest a dynamical bulk-surface correspondence. The topological phase is then classified by a dynamical topological invariant measured from the emergent dynamical field on the BISs. Applications to quenching experiments on feasible models are proposed and studied. The dynamical detection with high precision of the topological quantum physics has been achieved in experiments. We generalize this theory to correlated topological phase by quenching the spin-1/2 topological Haldane-Hubbard model. Novel correlation effects are shown in the non-equilibrium quantum dynamics for real spin and pseudospin spaces, with which both the topological phase and conventional magnetic order can be detected. These results may facilitate the experimental investigation of correlated topological physics.

邀 请 人：刘伍明（电话：8264 9249）

联 系 人：李园园（电话：8264 9364）