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arXiv · 1803.04110

Simultaneous Observation of Topological Edge State and Exceptional Point in an Open and Non-Hermitian System

Weiwei Zhu·Xinsheng Fang·Dongting Li·Yong Sun·Yong Li·Yun Jing·Hong Chen
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Abstract

This paper reports on the experimental observation of topologically protected edge state and exceptional point in an open and Non-Hermitian system. While the theoretical underpinning is generic to wave physics, the simulations and experiments are performed for an acoustic system whose structure has non-trivial topological properties that can be characterized by the Chern number provided that a synthetic dimension is introduced. Unidirectional reectionless propagation, a hallmark of exceptional point, is unambiguously observed in both simulations and experiments.

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Weiwei Zhu, Xinsheng Fang, Dongting Li, Yong Sun, Yong Li, Yun Jing, Hong Chen. 2018-03-12. Simultaneous Observation of Topological Edge State and Exceptional Point in an Open and Non-Hermitian System. https://doi.org/10.1103/physrevlett.121.124501

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