Model non-Hermitian topological operators without skin effect
- URL: http://arxiv.org/abs/2309.12310v1
- Date: Thu, 21 Sep 2023 17:59:29 GMT
- Title: Model non-Hermitian topological operators without skin effect
- Authors: Daniel J. Salib, Sanjib Kumar Das, Bitan Roy
- Abstract summary: We propose a principle of constructing non-Hermitian (NH) operators for insulating and gapless topological phases in any dimension.
We showcase these general and robust outcomes for NH topological insulators in $d=1,2$ and $3$, as well as for NH topological Dirac, Weyl and nodal-loop semimetals.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We propose a general principle of constructing non-Hermitian (NH) operators
for insulating and gapless topological phases in any dimension ($d$) that over
an extended NH parameter regime feature real eigenvalues and zero-energy
topological boundary modes, when in particular their Hermitian cousins are also
topological. However, the topological zero modes disappear when the NH
operators accommodate complex eigenvalues. These systems are always devoid of
NH skin effects, thereby extending the realm of the bulk-boundary
correspondence to NH systems in terms of solely the left or right zero-energy
boundary localized eigenmodes. We showcase these general and robust outcomes
for NH topological insulators in $d=1,2$ and $3$, encompassing their
higher-order incarnations, as well as for NH topological Dirac, Weyl and
nodal-loop semimetals. Possible realizations of proposed NH topological phases
in designer materials, optical lattices and classical metamaterials are
highlighted.
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