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arXiv · 1910.02878

Topological Origin of Non-Hermitian Skin Effects

Nobuyuki Okuma·Kohei Kawabata·Ken Shiozaki·Masatoshi Sato
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Abstract

A unique feature of non-Hermitian systems is the skin effect, which is the extreme sensitivity to the boundary conditions. Here, we reveal that the skin effect originates from intrinsic non-Hermitian topology. Such a topological origin not merely explains the universal feature of the known skin effect, but also leads to new types of the skin effects---symmetry-protected skin effects. In particular, we discover the $\mathbb{Z}_{2}$ skin effect protected by time-reversal symmetry. On the basis of topological classification, we also discuss possible other skin effects in arbitrary dimensions. Our work provides a unified understanding about the bulk-boundary correspondence and the skin effects in non-Hermitian systems.

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Nobuyuki Okuma, Kohei Kawabata, Ken Shiozaki, Masatoshi Sato. 2020-02-26. Topological Origin of Non-Hermitian Skin Effects. https://doi.org/10.1103/physrevlett.124.086801

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