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arXiv · 2403.13521

Hybrid skin-topological effect induced by eight-site cells and arbitrary adjustment of the localization of topological edge states

Abstract

The hybrid skin-topological effect (HSTE) in non-Hermitian systems exhibits both the skin effect and topological protection, offering a novel mechanism for the localization of topological edge states (TESs) in electrons, circuits, and photons. However, it remains unclear whether the HSTE can be realized in quasicrystals, and the unique structure of quasicrystals with multi-site cells may provide novel localization phenomena for TESs induced by the HSTE. We propose an eight-site cell in two-dimensional quasicrystals and realize the HSTE with eight-site nonreciprocal intracell hoppings. Furthermore, we can arbitrarily adjust the eigenfield distributions of the TESs and discover domain walls associated with effective dissipation and their correlation with localization. We present a new scheme to precisely adjust the energy distribution in non-Hermitian quasicrystals with arbitrary polygonal outer boundaries.

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Jianzhi Chen, Aoqian Shi, Yuchen Peng, Peng Peng, Jianjun Liu. 2024-03-20. Hybrid skin-topological effect induced by eight-site cells and arbitrary adjustment of the localization of topological edge states. https://doi.org/10.1088/0256-307x%2F41%2F3%2F037103

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