Efficient acousto-optic crystal, TIInS2: acoustic and elastic anisotropy

We have studied experimentally the acoustic wave velocities for TIInS2 crystals and determined all components of their elastic stiffness and compliance tensors. It has been found that TIInS2 reveals small elastic anisotropy with respect to normal mechanical stresses. The compliance components S-44 and S-55 are very large, thus suggesting that the TIInS2 crystals are extremely compliant to the shear stresses in the cleavage plane. We have also revealed that the velocities of some of the quasi-transverse waves are very low (similar to 725 m/s), leading to extremely high acousto-optic figures of merit (similar to 2200-9000 x 10(-15) s(3)/kg). This implies that the crystals under study can prove to be a very efficient acousto-optic material. (C) 2017 Optical Society of America