主讲人：朱小宇 副教授（西安交通大学）

题目：Bulk-boundary correspondence in higher-order topological superconductors

时间：2024年4月11日（周四）上午10：30

地 点：理工楼1215

联系人：贾伟

报告摘要：

Higher-order topological superconductors are characterized by Majorana modes localized at corners or hinges. Topological phase transitions in these higher-order phases can be driven by variations in a bulk parameter without closing the bulk gap. This presents a challenge in establishing a direct bulk-boundary correspondence, as conventional bulk invariants change only upon the closure of the bulk gap. In this talk, I will introduce our recent studies of two-dimensional higher-order topological superconductors in D, DIII and BDI symmetry classes. We demonstrate that in certain phases, a pair of topological invariants that are derived from Fermi level crossings can be used to characterize higher-order topology. These invariants may change with the closure of either bulk or edge gaps, thereby providing a clear demonstration of bulk-boundary correspondence in these higher-order phases.

个人简介：

朱小宇，西安交通大学物理学院副教授。2011年和2016年分别在南京大学取得学士和博士学位，之后入职西安交通大学。主要从事凝聚态物理中拓扑物态的理论研究，近年来比较关注高阶拓扑体系。