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Maximum Willis Coupling in Acoustic Scatterers

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 نشر من قبل Li Quan
 تاريخ النشر 2017
  مجال البحث فيزياء
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Willis coupling in acoustic materials defines the cross-coupling between strain and velocity, analogous to bianisotropic phenomena in electromagnetics. While these effects have been garnering significant attention in recent years, to date their effects have been considered mostly perturbative. Here, we derive general bounds on the Willis response of acoustic scatterers, show that they can become dominant in suitably designed scatterers, and outline a systematic venue for the realistic implementation of maximally bianisotropic inclusions. We then employ these inclusions to realize acoustic metasurfaces for sound bending with unitary efficiency.



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