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Optical non-Hermitian skin effect in uniform media

Taiki Yoda1, Yuto Moritake1, Kenta Takata2,3, Kazuki Yokomizo4, Shuichi Murakami1, and Masaya Notomi1,2,3,*

  • *Contact author: notomi@phys.sci.isct.ac.jp
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Phys. Rev. Research 7, 033214 – Published 3 September, 2025

DOI: https://doi.org/10.1103/3tlp-16mc

Abstract

Non-Hermitian skin effect (NHSE), which is a localization phenomenon in non-Hermitian systems, has recently been of great interest. Most previous works in various systems studied periodic systems. However, electromagnetic waves do not feel the periodicity of a system if the wavelength is sufficiently long, and it has not been clear that electromagnetic waves exhibit the localization caused by the non-Hermiticity itself even in uniform systems without the periodicity. Here, we establish the theory of the optical NHSE in non-Hermitian uniform media and show that the optical NHSE occurs even in uniform media. We apply our theory to subwavelength metamaterials and demonstrate the existence of a non-Hermitian skin mode in a multilayer metamaterial. Finally, we propose a concept of a stationarily excited skin mode to describe a lossy system under stationary excitation with real excitation frequency.

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Phys. Rev. Research 7, 033214– Published 3 September, 2025
  • Received 17 March 2023
  • Accepted 5 August 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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