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arXiv · 2209.15192

Sound non-reciprocity based on synthetic magnetism

Zhaoxian Chen·Zhengwei Li·Jingkai Weng·Bin Liang·Yanqing Lu·Jianchun Cheng·Andrea Alu
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Abstract

Synthetic magnetism has been recently realized using spatiotemporal modulation patterns, producing non-reciprocal steering of charge-neutral particles such as photons and phonons. Here, we design and experimentally demonstrate a non-reciprocal acoustic system composed of three compact cavities interlinked with both dynamic and static couplings, in which phase-correlated modulations induce a synthetic magnetic flux that breaks time-reversal symmetry. Within the rotating wave approximation, the transport properties of the system are controlled to efficiently realize large non-reciprocal acoustic transport. By optimizing the coupling strengths and modulation phases, we achieve frequency-preserved unidirectional transport with 45-dB isolation ratio and 0.85 forward transmission. Our results open to the realization of acoustic nonreciprocal technologies with high efficiency and large isolation, and offer a route towards Floquet topological insulators for sound.

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Zhaoxian Chen, Zhengwei Li, Jingkai Weng, Bin Liang, Yanqing Lu, Jianchun Cheng, Andrea Alu. 2022-09-30. Sound non-reciprocity based on synthetic magnetism. https://arxiv.org/abs/2209.15192

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