Acoustic Properties of Two-Dimensional Phononic Crystals Based on Fused Silica

We examine acoustic properties of two-dimensional squire-lattice phononic crystals based on fused silica. Dispersion relations of acoustic waves were computed with the finite element method. It is found that at relatively low frequencies, there are always three acoustic modes propagating inside a phononic crystal. Cross sections of acoustic slowness surfaces are calculated by considering dispersion relations. The influence of the unit cell parameters on the acoustic characteristics of a phononic crystal is considered. The analysis is carried out in order to assess a possibility of using phononic crystals in acousto-optic devices.