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arXiv · 1811.04130

Non-reciprocal sound propagation in space-time modulated media

Junfei Li·Chen Shen·Yangbo Xie·Steven A. Cummer
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Abstract

Realization of non-reciprocal devices, such as isolators and circulators, is of fundamental importance in microwave and photonic communication systems. This can be achieved by breaking time-reversal symmetry in the system or exploiting nonlinearity and topological effects. However, exploration of non-reciprocal devices remains scarce in acoustic systems. In this work, sound propagation in a space-time modulated medium is theoretically studied. Finite-difference time-domain (FDTD) simulations are carried out to verify the results. Functionalities such as mode conversion, parametric amplification and phase conjugation are demonstrated.

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Junfei Li, Chen Shen, Yangbo Xie, Steven A. Cummer. 2018-10-20. Non-reciprocal sound propagation in space-time modulated media. https://doi.org/10.1103/physrevb.99.144311

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