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arXiv · 2205.10317

Unidirectional edge modes in time-modulated metamaterials

Habib Ammari·Jinghao Cao
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Abstract

We prove the possibility of achieving unidirectional edge modes in time-modulated supercell structures. Such finite structures consist of two trimers repeated periodically. Because of their symmetry, they admit degenerate edge eigenspaces. When the trimers are time-modulated with two opposite orientations, the degenerate eigenspace splits into two one-dimensional eigenspaces described by an analytical formula, each corresponds to a mode which is localized at one edge of the structure. Our results on the localization and stability of these edge modes with respect to fluctuations in the time-modulation amplitude are illustrated by several numerical simulations.

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Habib Ammari, Jinghao Cao. 2022-05-18. Unidirectional edge modes in time-modulated metamaterials. https://arxiv.org/abs/2205.10317

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