Related papers: Anomalous features of non-Hermitian topological states

Anomalous features of non-Hermitian topological states

URL: http://arxiv.org/abs/2002.11105v1
Date: Mon, 24 Feb 2020 20:10:57 GMT
Title: Anomalous features of non-Hermitian topological states
Authors: C. Yuce
Abstract summary: We consider a one dimensional nonreciprocal Hamiltonian and show that topological robustness can be practically lost for a linear combination of eigenstates in non-Hermitian systems. 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.
Score: 0.0
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
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.

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