Elliptic polarization of acoustic waves in crystals

In this work we present experimental and theoretical studies of elliptic polarization of acoustic waves in crystals of lithium tantalate (LiTaO 3 ) and gadolinium-gallium garnet (GGG). The elliptically polarized waves can be obtained by superposition of two transverse waves with mutually perpendicular polarizations, propagating with slightly different velocities. The change of velocity of interacting waves can be obtained by the study of wave propagation in directions somewhat different than the pure-mode ones or by location of the crystal in an electric field. Experiments were performed using Bragg acousto-optical interaction. The transverse acoustic waves were generated by an X-cut transducer made from LiNbO 3 crystal.