Ultrasonic attenuation in BiSrCaCuO crystalline superconductor

Temperature dependencies of acoustic loss and Young modulus of Bi2Sr2CaCu2O8 high temperature superconductor were measured by a composite-bar resonator method at 99 and 156 kHz and at temperatures between 80 and 300 K. The two main relaxation peaks near 170 and 230 K were ascribed to the electronic and the oxygen displacement structural transitions, with the activation energies of 0.1 and 0.35 eV, respectively