Directional surface acoustic waves in noncentrosymmetric gratings

Spatial distribution of surface Rayleigh acoustic wave propagating along the surface of GaAs semiconductor covered by a periodic grating of gold stripes is calculated. We demonstrated that when the lattice has no center of spatial inversion the distribution of deformation for the surface wave with the Bloch wave vector $k_x$ = 0 is asymmetric and characterized by nonzero mean momentum in the interface plane and nonzero degree of transverse polarization in the plane perpendicular to the surface.