Two-Dimensional Chern Insulator with Topological Protection in Non-Hermitian Systems

Abstract

Topologically protected two-dimensional Chern insulators (2D Chern insulators) in non-Hermitian systems have been a recent research hotspot in topological physics. Conventional topological insulators exhibit robust edge states under symmetry-preserving conditions, whereas non-Hermitian systems, when considering non-Hermitian effects such as gain and dissipation, may undergo significant changes in topological phases and edge state characteristics. This paper investigates how non-Hermitian effects influence the topologically protected phases of two-dimensional Chern insulators, particularly focusing on the evolution of Berry curvature, edge state stability, and topological invariants under non-Hermitian perturbations. Through a combination of experimental and numerical simulation methods, we analyzed the impact of various system parameters (e.g., non-Hermitian effect strength, external magnetic field, gain/loss coefficients) on topological protection, revealing the critical role of non-Hermitian effects in two-dimensional topological materials.