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Phononic crystals with planar defects

I. E. Psarobas·N. Stefanou·A. Modinos
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Abstract

We study the effect of planar defects in phononic crystals of spherical scatterers. It is shown that a plane of impurity spheres introduces modes of vibration of the elastic field localized on this plane at frequencies within a frequency gap of a pure phononic crystal; these show up as sharp resonances in the transmittance of elastic waves incident on a slab of the crystal. A periodic arrangement of impurity planes along a given direction creates narrow impurity bands with a width which depends on the position of these bands within the frequency gap of the pure crystal and on the separation between the impurity planes. We show how a slight deviation from periodicity (one impurity plane is different from the rest) reduces dramatically the transmittance of elastic waves incident on a slab of the crystal.

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I. E. Psarobas, N. Stefanou, A. Modinos. 2000-05-12. Phononic crystals with planar defects. https://doi.org/10.1103/physrevb.62.5536

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