Vibrational properties of (0Â 0Â 1) III-V nitride superlattices

We study the acoustic waves of superlattices grown along the [0 0 1] direction and formed by slabs of cubic III-V nitride. We consider structures formed by combining AlN, GaN and InN in the zinc-blende structure because of the possible applications of these materials. The anisotropy of the materials has been taken into account and the different propagation directions including symmetry directions and general directions have been considered. The dispersion relations for these propagation directions have been obtained. The evolution of gaps along the propagation directions is studied. Total gaps for some propagation directions and frequency ranges are found in GaN-InN superlattices.