Measurements of acoustical physical constants for Ca3Nb(Ga0.75Al0.25)3Si2O14 single crystal using the ultrasonic microspectroscopy system

Acoustical physical constants were experimentally determined for Al-substituted Ca₃NbGa₃Si₂O₁₄ (CNGAS) single crystal for the first time. Several plate specimens of the X-, Y-, Z-, 40.24°Y-, and 144.98°Y-cut were prepared from a CNGAS single crystal ingot grown by Czochralski technique. Elastic constants, piezoelectric constants, and their temperature coefficients were determined from longitudinal wave and shear wave velocities measured for the CNGAS specimens at around room temperature using the ultrasonic micro-spectroscopy (UMS) system. Dielectric constants, density, and coefficients of thermal expansion were also measured. It was demonstrated that the determined constants could provide calculation accuracy within ±0.12% in leaky surface acoustic wave (LSAW) velocity.