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arXiv · 2305.08313

Realization of a Z classified chiral-symmetric higher-order topological insulator in a coupling-inversion acoustic crystal

Dongyi Wang·Yuanchen Deng·Mourad Oudich·Wladimir A. Benalcazar·Guancong Ma·Yun Jing
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Abstract

Higher-order topological band theory has transformed the landscape of topological phases in quantum and classical systems. Here, we experimentally demonstrate a two-dimensional (2D) higher-order topological phase (HOTP), referred to as the multiple chiral topological phase (MCTP), which is protected by a multipole chiral number (MCN). Our realization differs from previous HOTPs in that it possesses a larger-than-unity MCN, which arises when the nearest-neighbor couplings (NNCs) are weaker than long-range couplings (LRCs). Our phase has an MCN of 4, protecting the existence of 4 mid-gap topological corner modes (TCMs) at each corner. The multiple TCMs demonstrated here could lead to enhanced quantum-inspired devices for sensing and computing. Our study also highlights the rich and untapped potential of LRC manipulation for future research in topological phases.

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Dongyi Wang, Yuanchen Deng, Mourad Oudich, Wladimir A. Benalcazar, Guancong Ma, Yun Jing. 2023-05-15. Realization of a Z classified chiral-symmetric higher-order topological insulator in a coupling-inversion acoustic crystal. https://doi.org/10.1103/physrevlett.131.157201

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