Investigation of Surface and Pseudo-Surface Acoustic Wave Propagation in La3Ga5SiO14 Crystal by X-Ray Diffraction

Features of the surface acoustic wave(SAW) and pseudo-surface acoustic waves (PSAW) propagation in a disordered piezoelectric crystal La3Ga5SiO14 (LGS, langasite) were studied using X-ray diffraction at the BESSY II synchrotron radiation source. The process of acoustic wave propagation in Z-cut of an LGS crystal was investigated. It has been shown that SAW and PSAW have different acoustic wave velocities, different amplitudes, and different power flow angles of acoustic energy propagation, which differ not only in value but also in sign.