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arXiv · 2601.19855

Non-Hermitian Fabry-P\'erot Resonances

Habib Ammari·Erik Orvehed Hiltunen·Bowen Li·Ping Liu·Jiayu Qiu·Yingjie Shao·Alexander Uhlmann
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Abstract

We characterise non-Hermitian Fabry-P\'erot resonances in high-contrast resonator systems and study the properties of their associated resonant modes from continuous differential models. We consider two non-Hermitian effects: the exceptional point degeneracy and the skin effect induced by imaginary gauge potentials. Using the propagation matrix formalism, we characterise these two non-Hermitian effects beyond the subwavelength regime. This analysis allows us to (i) establish the existence of exceptional points purely from radiation conditions and to (ii) prove that the non-Hermitian skin effect applies uniformly across resonant modes, yielding broadband edge localisation.

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Habib Ammari, Erik Orvehed Hiltunen, Bowen Li, Ping Liu, Jiayu Qiu, Yingjie Shao, Alexander Uhlmann. 2026-01-27. Non-Hermitian Fabry-P\'erot Resonances. https://arxiv.org/abs/2601.19855

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