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arXiv · 2208.11712

Magnetic Flux Response of Non-Hermitian Topological Phases

M. Michael Denner·Frank Schindler
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Abstract

We derive the response of non-Hermitian topological phases with intrinsic point gap topology to localized magnetic flux insertions. In two spatial dimensions, we identify the necessary and sufficient conditions for a flux skin effect that localizes an extensive number of in-gap modes at a flux core. In three dimensions, we furthermore establish the existence of: a flux spectral jump, where flux tube insertion fills up the entire point gap only at a single parallel crystal momentum; a higher-order flux skin effect, which occurs at the ends of flux tubes in presence of pseudo-inversion symmetry; and a flux Majorana mode that represents a spectrally isolated mid-gap state in the complex energy plane. We uniquely associate each non-Hermitian symmetry class with intrinsic point gap topology with one of these cases or a trivial flux response, and discuss possible experimental realizations.

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M. Michael Denner, Frank Schindler. 2023-09-01. Magnetic Flux Response of Non-Hermitian Topological Phases. https://doi.org/10.21468/scipostphys.14.5.107

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