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arXiv · 2306.03705

Photonic Floquet skin-topological effect

Yeyang Sun·Xiangrui Hou·Tuo Wan·Fangyu Wang·Shiyao Zhu·Zhichao Ruan·Zhaoju Yang
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Abstract

Non-Hermitian skin effect and photonic topological edge states are of great interest in non-Hermitian physics and optics. However, the interplay between them is largly unexplored. Here, we propose and demonstrate experimentally the non-Hermitian skin effect that constructed from the nonreciprocal flow of Floquet topological edge states, which can be dubbed 'Floquet skin-topological effect'. We first show the non-Hermitian skin effect can be induced by pure loss when the one-dimensional (1D) system is periodically driven. Next, based on a two-dimensional (2D) Floquet topological photonic lattice with structured loss, we investigate the interaction between the non-Hermiticity and the topological edge states. We observe that all the one-way edge states are imposed onto specific corners, featuring both the non-Hermitian skin effect and topological edge states. Furthermore, a topological switch for the skin-topological effect is presented by utilizing the gap-closing mechanism. Our experiment paves the way of realizing non-Hermitian topological effects in nonlinear and quantum regimes.

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Yeyang Sun, Xiangrui Hou, Tuo Wan, Fangyu Wang, Shiyao Zhu, Zhichao Ruan, Zhaoju Yang. 2023-06-06. Photonic Floquet skin-topological effect. https://arxiv.org/abs/2306.03705

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