Abstract

The depolarization of acousto-optic light scattering was determined from the contribution of a strong elasto-optic polarization driven amplitude. When compared to the surface corrugation amplitude, the elasto-optic amplitude offered the greatest contribution to depolarization of the scattered light in the region of near-zero incidence angle. In this investigation, the elasto-optic amplitude component was a cumulative part of the depolarization effect owing strongly to the cosine term in the incident light wave-vector. For S- and P-incident optical states, the elasto-optic amplitude term contribution was significant when both coplanar and non-coplanar acousto-optic incidence angles were also near zero with decreasing effectiveness away from zero. The angular depolarization dependence appears to relate directly with relative magnitudes of the surface acoustic wave vector, K, and the surface projection of the optical wave vector, k. Consequently, the depolarization dependence on the incidence angle relates to a perspective view of K as it appears to k when viewed at near normal incidence. Under these conditions, the values of K and k are interchangeable and the strong cross-coupling between polarization states can be predicted.

© 1990 Optical Society of America