Shear Surface Acoustic Waves in Twinned Piezoelectric Crystals of the $$\bar {6}$$m2 Symmetry Class

Abstract

Shear surface acoustic waves, whose existence is due to the difference in the signs of piezoelectric modulus tensors of adjoining halves of crystal, are studied on flat interfaces of twinned hexagonal piezoelectric crystals of the $$\bar {6}$$m2 symmetry class. In this case, the inversion axis $$\bar {6}$$ is perpendicular to the interface between the halves. It is shown that, at a weak piezoelectric effect, the characteristic penetration depth of these waves is inversely proportional to the square of component e222 and may significantly exceed the length of the surface wave.