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arXiv · 1102.4679

Elastic metamaterials with simultaneously negative effective shear modulus and mass density

Ying Wu·Yun Lai·Zhao-Qing Zhang
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Abstract

We propose a type of elastic metamaterial comprising fluid-solid composite inclusions which can possess negative shear modulus and negative mass density over a large frequency region. Such a solid metamaterial has a unique elastic property that only transverse waves can propagate with a negative dispersion while longitudinal waves are forbidden. This leads to many interesting phenomena such as negative refraction, which is demonstrated by using a wedge sample, and a significant amount of mode conversion from transverse waves to longitudinal waves that cannot occur on the interface of two natural solids.

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Ying Wu, Yun Lai, Zhao-Qing Zhang. 2011-02-23. Elastic metamaterials with simultaneously negative effective shear modulus and mass density. https://doi.org/10.1103/physrevlett.107.105506

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