ANALYSIS OF ACOUSTIC WAVE FIELDS IN La3Ga5SiO14 CRYSTALS USING X-RAY TOPOGRAPHY

摘要

Fields of standing surface acoustic waves (SAVs) in X-, Y-, and (022)-cuts of lanthanum gallium silicate crystal (La3Ga5SiO14, lan-gasite, LGS) were studied using high-resolution X-ray topography. SAV amplitudes and power flow angles were determined. The influence of crystal structure defects (twins, block structures, growth bands, and .F-centers) on propagation of ultrasonic superlattices was studied. It was shown that only twins and jF-centers result in strong distortions of acoustic wave fields in LGS crystals.