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arXiv · 2008.11597

Band-gap tuning in 2D spatiotemporal phononic crystals

D. Psiachos·M. M. Sigalas
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Abstract

We investigate the effect of small spatiotemporal modulations in subwavelength-dimensioned phononic crystals with large band gaps, on the frequency spectrum for elastic waves polarized in the plane of periodicity. When the radius of cylinders periodically placed inside a matrix of highly-contrasting elastic properties is time-varying, we find that due to the appearance of frequency harmonics throughout the spectrum, the notion of a band gap is destroyed in general, although with the appropriate tuning of parameters, in particular the modulation frequency, it is possible that some band-gap region is retained, making such systems possible candidates for tunable bandpass filters or phononic isolators, accordingly, and for sensor applications.

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D. Psiachos, M. M. Sigalas. 2021-01-15. Band-gap tuning in 2D spatiotemporal phononic crystals. https://doi.org/10.1103/physrevapplied.15.014022

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