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arXiv · 2308.00776

Lack of near-sightedness principle in non-Hermitian systems

Helene Spring·Viktor Könye·Anton R. Akhmerov·Ion Cosma Fulga
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Abstract

The non-Hermitian skin effect is a phenomenon in which an extensive number of states accumulates at the boundaries of a system. It has been associated to nontrivial topology, with nonzero bulk invariants predicting its appearance and its position in real space. Here, we demonstrate that the non-Hermitian skin effect has weaker bulk-edge correspondence than topological insulators: when translation symmetry is broken by a single non-Hermitian impurity, skin modes are depleted at the boundary and accumulate at the impurity site, without changing any bulk invariant. Similarly, a single non-Hermitian impurity may deplete the states from a region of Hermitian bulk.

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Helene Spring, Viktor Könye, Anton R. Akhmerov, Ion Cosma Fulga. 2023-08-01. Lack of near-sightedness principle in non-Hermitian systems. https://doi.org/10.21468/scipostphys.17.6.153

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