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2021-12-24

Non-Hermitian Skin Effect and Delocalized Edge States in Photonic Crystals with Anomalous Parity-Time Symmetry

By Qinghui Yan, Hongsheng Chen, and Yihao Yang
Progress In Electromagnetics Research, Vol. 172, 33-40, 2021
doi:10.2528/PIER21111602

Abstract

Non-Hermitian skin effect denotes the exponential localization of a large number of eigen-states at boundaries 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.

Citation


Qinghui Yan, Hongsheng Chen, and Yihao Yang, "Non-Hermitian Skin Effect and Delocalized Edge States in Photonic Crystals with Anomalous Parity-Time Symmetry," Progress In Electromagnetics Research, Vol. 172, 33-40, 2021.
doi:10.2528/PIER21111602
http://jpier.org/PIER/pier.php?paper=21111602

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