Non-Hermitian spectral flows and Berry-Chern monopoles
- URL: http://arxiv.org/abs/2209.03876v1
- Date: Thu, 8 Sep 2022 15:27:49 GMT
- Title: Non-Hermitian spectral flows and Berry-Chern monopoles
- Authors: Lucien Jezequel, Pierre Delplace
- Abstract summary: We show a non-Hermitian generalization of the correspondence between the spectral flow and the topological charges of band crossing points.
A class of non-Hermitian Hamiltonians that display a complex-valued spectral flow is built by deforming an Hermitian model.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We propose a non-Hermitian generalization of the correspondence between the
spectral flow and the topological charges of band crossing points (Berry-Chern
monopoles). A class of non-Hermitian Hamiltonians that display a complex-valued
spectral flow is built by deforming an Hermitian model while preserving its
analytical index. We relate those spectral flows to a generalized Chern number
that we show to be equal to that of the Hermitian case, provided a line gap
exists. In the absence of a line gap, the system still displays a spectral flow
whose topology can be captured by exploiting an emergent pseudo-Hermitian
symmetry.
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