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Published on: August 27, 2013
Simultaneous Observation of a Topological Edge State and Exceptional Point in an Open and Non-Hermitian Acoustic
Weiwei Zhu1,2, Xinsheng Fang1,2, Dongting Li1,2
1MOE Key Laboratory of Advanced Micro-Structured Materials, School of Physics Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China.
Abstract:
This Letter reports on the experimental observation of a topologically protected edge state and exceptional point in an open and non-Hermitian (lossy) acoustic system. Although the theoretical underpinning is generic to wave physics, the simulations and experiments are performed for an acoustic system. It has nontrivial topological properties that can be characterized by the Chern number provided that a synthetic dimension is introduced. Unidirectional reflectionless propagation, a hallmark of exceptional points, is unambiguously observed in both simulations and experiments.
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