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arXiv · 2111.08213

Non-Hermitian skin effect and delocalized edge states in photonic crystals with anomalous parity-time symmetry

Qinghui Yan·Hongsheng Chen·Yihao Yang
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Abstract

Non-Hermitian skin effect denotes the exponential localization of a large number of eigen-states in a non-Hermitian lattice under open boundary conditions. Such a non-Hermiticity-induced skin effect can offset the penetration depth of in-gap edge states, leading to counterintuitive delocalized edge modes, which have not been studied in a realistic photonic system such as photonic crystals. Here, we analytically reveal the non-Hermitian skin effect and the delocalized edge states in Maxwell's equations for non-Hermitian chiral photonic crystals with anomalous parity-time symmetry. Remarkably, we rigorously prove that the penetration depth of the edge states is inversely proportional to the frequency and the real part of the chirality. Our findings pave a way towards exploring novel non-Hermitian phenomena and applications in continuous Maxwell's equations.

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Qinghui Yan, Hongsheng Chen, Yihao Yang. 2021-11-16. Non-Hermitian skin effect and delocalized edge states in photonic crystals with anomalous parity-time symmetry. https://arxiv.org/abs/2111.08213

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