Generation of acoustic vortices and acousto-optic interactions with acoustic vortex beams.

We demonstrate the generation of acoustic vortex beams with the aid of an acoustic spiral phase plate and an acoustic grating having a fork-like bifurcation of its slits. The acoustic vortex beam generated in this manner influences the particles floating on a water surface and rotates them. Our experiments show that the intensity of the acoustic vortex beam increases from zero in its center to a certain maximal value near the shell of the beam.

Experimental determination of full matrices of the piezo-optic and elasto-optic coefficients for PbGeO crystals.

We determine full matrices of piezo-optic and elasto-optic coefficients for lead germanate crystals, , using Dixon-Cohen and interferometric methods. Two different types of samples are studied, single- and multi-domain. We show that the correct data for the crystals can be obtained only with single-domain samples, since the domain structure induces a number of features that make the final results unreliable.

Acousto-optic interaction between circularly polarized optical eigenwaves: example of AgGaS crystals.

We analyze acousto-optic (AO) diffraction occurring at the light wavelength of a so-called "isotropic point" in AgGaS crystals. It is shown that a natural optical activity, which manifests itself as circular birefringence at the isotropic point, can lead to two different types of AO Bragg diffraction, isotropic and anisotropic. The first type concerns the interaction of circularly polarized optical eigenwaves with the same sign of rotations of their electric-field vectors.

Generation of an optical vortex array in the course of acousto-optic diffraction.

Generation of an array of optical vortices (OVs) with fractional charges under the condition of acousto-optic Bragg diffraction is revealed experimentally. The OVs emerge in a wide diffracted optical beam due to reflection from a thick acousto-optic grating that contains bifurcated fringes of acoustic waves (AWs). Changes in the AW frequency lead to deflection of the wide optical beam containing the OV array.

Piezo-, elasto- and acousto-optic properties of TlAsS crystals.

Complete matrices of piezo-optic and elasto-optic tensors are experimentally determined for TlAsS crystals. It is revealed that the piezo-optic coefficients are very high, ∼10  N/m in the order of magnitude. This implies that TlAsS can be referred to the best piezo-optic materials.

Acoustic anisotropy of acoustooptic TI(3)AsS(4) crystals.

We present comprehensive experimental measurements and analysis of anisotropy of the acoustic wave velocities for TI(3)AsS(4) crystals, including the obliquity and nonorthogonality of the acoustic waves, and the deviations from purely longitudinal and transverse polarization types. We have found that the crystals under analysis are characterized by rather low transverse wave velocities v(23) and v(32), which are both equal to 630 m/s. It is shown that the efficiency of acoustooptic (AO) interactions in TI(3)AsS(4) can be notably increased when providing anisotropic interaction with the slowest transverse acoustic wave.