Acoustic diffraction and the electrostrictive transducer

Abstract

Permanent photoinduced periodic space-charge gratings in LiNbO3 are used to modulate the optical refractive index and diffract light. Since this periodic space-charge distribution is the source of a periodic electric field, these gratings ought to modulate the elastic constants and diffract bulk acoustic waves. In addition, these gratings ought to modulate the piezoelectric constant via the electrostrictive effect and behave as distributed transducers for bulk acoustic waves. These phenomena should be observable for frequencies near 10 GHz with grating amplitudes reported in the literature. Some applications of these phenomena are discussed.