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Reflected continuously tunable acoustic metasurface with rotatable space coiling-up structure

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 نشر من قبل Pai Peng
 تاريخ النشر 2020
  مجال البحث فيزياء
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In this paper, we propose a continuously tunable acoustic metasurface composed of identical anisotropic resonant units, each of which contains a rigid pedestal and a rotatable inclusion with space coiling-up structure. The metasurface can manipulate the reflected phase by adjusting the rotational angle of inclusion. The theoretical analysis shows that the polarization-dependent phase change can be induced by the even-order standing wave modes inside inclusion. By utilizing the rotatable inclusion, we design a tunable acoustic carpet cloaking device, which works with a wide range for incident angle. When incident waves come from different directions, the cloaking effect can be obtained by arrange the rotational angle of each inclusion.

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