Ultrasonic studies of phase transitions in the tin telluride-germanium telluride system Sn_xGe_1-xTe

Abstract

Single crystals of SnxGe1-xTe(x=0.75 to 0.91) have been grown by the bridgman method for ultrasonic measurements of the sound velocities and the attenuation near the transition temperature. The results can be qualitatively interpreted in terms of an electrostrictive-type coupling between strain and order parameter and a critical behaviour of the specific heat. A tricritical point is expected for compositions x below the range studied.