Anomalous features of non-Hermitian topological states

Abstract

Topological states in non-Hermitian systems are known to exhibit some anomalous features. Here, we find two new anomalous features of non-Hermitian topological states. We consider a one dimensional nonreciprocal Hamiltonian and show that topological robustness can be practically lost for a linear combination of topological eigenstates in non-Hermitian systems due to the non-Hermitian skin effect. We consider a two dimensional non-Hermitian Chern insulator and show that chirality of topological states can be broken at some parameters of the Hamiltonan. This implies that the topological states are no longer immune to backscattering in 2D.

arXiv commentTo appear Ann. of Phys

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Cited by in corpus (8)

• Nonlinear non-Hermitian skin effect
• Fourth-Order Exceptional Points in Correlated Quantum Many-Body Systems
• Non-Hermitian edge burst without skin localizations
• Eigenstate clustering around exceptional points
• Quasi-stationary solutions in non-Hermitian systems
• Spontaneous Formation of Exceptional Points at the Onset of Magnetism
• Bulk--Boundary Correspondence and Boundary Zero Modes in a Non-Hermitian Kitaev Chain Model
• Phase Diagram of a Non-Hermitian Chern Insulator: Destabilization of Chiral Edge States and Bulk-Boundary Correspondence