On the existence problem for localized acoustic waves on the interface between two piezocrystals

Abstract

The investigation of the existence problem for inhomogeneous acoustic waves on the interface between two piezocrystals of arbitrary anisotropy is performed on the basis of the surface impedance method. It is shown that not more than two localized waves may exist if two piezoelectric half-infinite spaces are in welded contact and the electrical boundary conditions require the electrical potential to vanish on the interface. However, if the normal projection of electrical induction is assumed to be zero on the interface, then at most one interfacial wave comes into existence. For two piezoelectric crystals in sliding contact at most three or at most two “slip” intrinsic waves may appear depending on the electrical boundary conditions. But if two piezocrystals are separated by an air gap, then not more than four inhomogeneous “gap” waves propagate along the gap. The existence problem for localized acoustic waves on the interface between two piezomagnetic crystals is also discussed.