Acoustic and elastic properties of Sn₂P₂S₆crystals

Abstract

We present the results concerned with acoustic and elastic properties of Sn(2)P(2)S(6) crystals. The complete matrices of elastic stiffness and compliance coefficients are determined in both the crystallographic coordinate system and the system associated with eigenvectors of the elastic stiffness tensor. The acoustic slowness surfaces are constructed and the propagation and polarization directions of the slowest acoustic waves promising for acousto-optic interactions are determined on this basis. The acoustic obliquity angle and the deviation of polarization of the acoustic waves from purely transverse or longitudinal states are quantitatively analysed.

On the acoustooptic efficiency of Pb2P2Se6 crystals. Acoustic and thermal studies

“…Besides, latter coordinate system rotates around the crystallographic b axis while the temperature changes. In our experiments we were able to determine the diagonal components 11  , 11  , and 33  of the thermal expansion coefficients. The error of determination of the thermal expansion coefficients was about ±10 -5 .…”

Acoustic and elastic anisotropy of acousto-optic Pb2P2Se6 crystals

“…Let us remind that a similar property is peculiar for the Sn 2 P 2 S 6 and Sn 2 P 2 Se 0.28 S 0.72 6 crystals [6,20,21]. In these crystals the slowest QL wave also propagates along the b axis.…”

Acoustooptic figure of merit for Sn2P2S6 crystals and the temperature dependences of acoustic wave velocities

“…We have shown in our recent work [10] that it is the transverse wave with the velocity 1550 120 m/s  which is the slowest for the Sn 2 P 2 S 6 crystals at the room temperature. One can easily estimate that, in case of AO interaction with this wave, the AOFM can increase four times, when compared with the value obtained in the work [8], if only the effective elastooptic coefficient remained approximately the same.…”