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arXiv · 2305.17853

Observation of non-Hermitian antichiral edge currents

Rui Ye·Yanyan He·Guangzhen Li·Luojia Wang·Xiaoxiong Wu·Xin Qiao·Yuanlin Zheng·Liang Jin·Da-Wei Wang·Luqi Yuan·Xianfeng Chen
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Abstract

Non-Hermitian topological photonics is of great interest in bridging topological matter with gain/dissipation engineering in optics. A key problem in this direction is the interplay between the effective gauge potential and the non-Hermiticity. Here we tackle this problem in a synthetic non-Hermitian Hall ladder and experimentally observe antichiral edge currents (ACECs) of photons, by tuning the locally uniform effective magnetic flux and the on-site gain/loss. Such ACECs provide a topological method to probe the signatures of the non-Hermitian skin effect (NHSE) from steady-state bulk dynamics. The universality of this method is verified by its generalization to three dimensions. This study paves a way to investigate exotic non-Hermitian topological physics and has potential applications in topological photonics engineering.

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Rui Ye, Yanyan He, Guangzhen Li, Luojia Wang, Xiaoxiong Wu, Xin Qiao, Yuanlin Zheng, Liang Jin, Da-Wei Wang, Luqi Yuan, Xianfeng Chen. 2023-05-29. Observation of non-Hermitian antichiral edge currents. https://doi.org/10.1038/s41377-024-01700-1

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