Topological states in non-Hermitian two-dimensional Su-Schrieffer-Heeger model

TL;DR

This paper presents a two-dimensional non-Hermitian topological insulator model based on the SSH framework, demonstrating real spectra and topological edge states, with potential for experimental realization.

Contribution

It introduces a novel 2D non-Hermitian SSH model with real spectra and topological edge states, expanding the understanding of non-Hermitian topological phases.

Findings

Existence of topological edge states in the band gap.

Introduction of a non-Hermitian polarization vector.

Potential for experimental realization of the model.

Abstract

A non-Hermitian topological insulator with real spectrum is interesting in the theory of non-Hermitian extension of topological systems. We find an experimentally realizable example of a two dimensional non-Hermitian topological insulator with real spectrum. We consider two-dimensional Su-Schrieffer-Heeger (SSH) model with gain and loss. We introduce non-Hermitian polarization vector to explore topological phase and show that topological edge states in the band gap exist in the system.