Acoustoelectric effects in reflection of leaky-wave-radiated bulk acoustic waves from piezoelectric crystal-conductive liquid interface.

The leaky surface acoustic wave (SAW) propagating along X-axis of Y-cut lithium tantalate crystal strongly radiates energy in the form of an obliquely propagating narrow bulk acoustic wave (BAW) beam. The reflection of this beam from the crystal-liquid interface has been investigated. The test liquids were solutions of potassium nitrate in distilled water and of lithium chloride in isopropyl alcohol with the conductivity varied by changing the solution concentration.

Surface acoustic wave response to optical absorption by graphene composite film.

Propagation of surface acoustic waves in YZ LiNbO3 overlaid with graphene flakes has been investigated and its optical response to illumination by 633-nm light from a He-Ne laser was studied. The heating of the sample surface caused by optical absorption by the graphene led to a downshift in the transmitted SAW phase caused by the wave velocity's dependence on temperature. The proposed simple model based on optothermal SAW phase modulation was found to be in good agreement with the experimental results.

Acousto-optic interaction with leaky surface acoustic waves in Y-cut LiTaO3 crystals.

The acousto-optic interaction with leaky surface acoustic wave radiation into the bulk of YX-cut LiTaO(3) crystals has been investigated. The light incidence and diffraction angles corresponding to the strongest acousto-optic interaction were calculated and measured as functions of the acoustic wave frequency. The dependencies of the diffracted light intensity on the amplitude of radio-frequency voltage applied to the interdigital transducer (IDT) were studied.

Control of light polarization by acousto-optic diffraction from leaky acoustic wave in LiNbO₃.

The acousto-optic control of light polarization due to diffraction by leaky acoustic waves in ZX-LiNbO₃ has been demonstrated. The randomly polarized light of 633 nm wavelength is converted by the anisotropic diffraction into two beams with mutually orthogonal polarizations, the relative intensities of which depend on the light incidence angle and acoustic frequency. Variation in acoustic frequency from 108 to 112 MHz rotates the polarization of the output optical beam by 90°.

Surface acoustic wave velocity in single-crystal AlN substrates.

The surface acoustic wave velocity has been measured on a-plane (c-propagation) and c-plane oriented bulk aluminum nitride (AlN) single crystals using the S11-parameter method in the frequency range 160-360 MHz. The SAW velocity is 5760 m/s for both orientations. From comparison of this value with the simulations using various elastic constants of AlN available in literature, we estimated the elastic constant C44 to be 122 +/- 1 GPa.