# Anisotropic mass density by two-dimensional acoustic metamaterials

@article{Torrent2008AnisotropicMD, title={Anisotropic mass density by two-dimensional acoustic metamaterials}, author={Daniel Torrent and Jos{\'e} S{\'a}nchez-Dehesa}, journal={New Journal of Physics}, year={2008}, volume={10}, pages={023004} }

We show that specially designed two-dimensional arrangements of full elastic cylinders embedded in a nonviscous fluid or gas define (in the homogenization limit) a new class of acoustic metamaterials characterized by a dynamical effective mass density that is anisotropic. Here, analytic expressions for the dynamical mass density and the effective sound velocity tensors are derived in the long wavelength limit. Both show an explicit dependence on the lattice filling fraction, the elastic…

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