Generalized bulk-edge correspondence for non-Hermitian topological systems

A modified periodic boundary condition adequate for non-Hermitian topological systems is proposed. Under this boundary condition, a topological number characterizing the system is defined in the same way as in the corresponding Hermitian system, and hence, at the cost of introducing an additional pa...

Full description

Saved in:
Bibliographic Details
Published in:Physical review. B 2019-10, Vol.100 (16), Article 165430
Main Authors: Imura, Ken-Ichiro, Takane, Yositake
Format: Article
Language:English
Subjects:
Boundary conditions
Parameter identification
Skin effect
Topology
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:A modified periodic boundary condition adequate for non-Hermitian topological systems is proposed. Under this boundary condition, a topological number characterizing the system is defined in the same way as in the corresponding Hermitian system, and hence, at the cost of introducing an additional parameter that characterizes the non-Hermitian skin effect, the idea of bulk-edge correspondence in the Hermitian limit can be applied almost as it is. We develop this framework through the analysis of a non-Hermitian Su-Schrieffer-Heeger model with chiral symmetry and prove the bulk-edge correspondence in a generalized parameter space. A finite region in this parameter space with a nontrivial pair of chiral winding numbers is identified as topologically nontrivial, indicating the existence of a topologically protected edge state under an open boundary.
ISSN:2469-9950
2469-9969
DOI:10.1103/PhysRevB.100.165430