Tao Liu

Theoretical Quantum Physics Laboratory
RIKEN
Japan

Second-Order Topological Phases in Non-Hermitian Systems

Recently, there has been a great deal of interest in studying topological phases of open systems governed by non-Hermitian operators, altering the nature of the usual bulk-boundary correspondence in topological systems. Meanwhile, in the context of Hermitian topological systems, the concept of topological insulators has been generalized to higher-order topological insulators. In contrast to conventional first-order topological phases, a d-dimensional second-order topological insulator (SOTI) can host topologically protected (d-2)-dimensional gapless boundary modes. In this talk, In this talk, I will start with an overview of non-Hermitian phenomena and higher-order topological phases. Then I will present our investigation of non-Hermitian seconder-order topological insulators.