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arXiv · 2403.05039

Tunable non-Hermitian skin effect via gain and loss

Wen-Cheng Jiang·Hong Wu·Jian Li·Qing-Xu Li·Jia-Ji Zhu
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Abstract

We investigate theoretically tunable non-Hermitian skin effect in systems with gain and loss, and find that bipolar (quadripolar) non-Hermitian skin effect characterized by topological invariants in one (two)-dimensional system. We also find the partial non-Hermitian skin effect with the coexistence of localized states and extended states. Both types of the non-Hermitian skin effect have not yet been predicted together in a single system. A feasible experimental scheme of our model is proposed to realize in electric circuits. Our investigation unveils a new type of non-Hermitian skin effect and enhance the tunability of the non-Hermitian systems by gain and loss other than the conventional non-reciprocal hopping.

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Wen-Cheng Jiang, Hong Wu, Jian Li, Qing-Xu Li, Jia-Ji Zhu. 2024-03-08. Tunable non-Hermitian skin effect via gain and loss. https://arxiv.org/abs/2403.05039

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