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arXiv · 2401.14071

Controlling surface acoustic waves (SAWs) via temporally graded metasurfaces

Jonatha Santini·Xingbo Pu·Antonio Palermo·Francesco Braghin·Emanuele Riva
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Abstract

In this manuscript, the temporal rainbow effect for surface acoustic waves (SAW) is illustrated through a temporal analog of space metagradings. We show that a time-modulated array of mechanical resonators induces a wavenumber-preserving frequency transformation which, in turn, dictates Rayleigh-to-Shear wave conversion. The process is unfolded through the adiabatic theorem, which allows us to delineate the transition between a solely frequency-converted wave packet and a temporally-driven mode conversion. In other words, our paper explores the role of time modulation in the context of elastic metasurfaces, and we envision our implementation to be suitable for designing a new family of SAW devices with frequency conversion, mode conversion, and unusual transport capabilities.

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Jonatha Santini, Xingbo Pu, Antonio Palermo, Francesco Braghin, Emanuele Riva. 2024-01-25. Controlling surface acoustic waves (SAWs) via temporally graded metasurfaces. https://arxiv.org/abs/2401.14071

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