Wideband light diffraction on bulk acoustic waves in uniaxial crystals

We study diffraction of light on ultrasonic waves, excited by a system of interdigitial transducers, in uniaxial crystals. We show that wideband acoustooptical diffraction in trigonal crystals in the presence of additional anisotropy differs significantly from the isotropy of diffraction on a shear ultrasonic wave in the absence of it. We establish that an exact Bragg angle correction in a wide frequency retuning range is achieved owing to electrically induced anisotropy in the external electric field.