Anomalies in the velocity of sound and in the elastic moduli near the superconducting transition of the ceramic YBa2Cu3O7
Golovashkin A. I. , Danilov V. A. , Ivanenko O. M. , Mitsen K. V. , Perepechko I.I.
The velocity of the longitudinal and transverse ultrasonic waves (2.4 MHz) in a superconducting ceramic YBa2Cu307 is measured over the temperature interval 4.2-300 K. The ultrasonic velocity of the longitudinal and transverse waves was found to behave anomalously in the neighborhood of the superconducting transition (93 K). The velocity of the longitudinal waves was also found to increase as the temperature was raised from 40 К to 65 K. The results of the measurements are used to calculate the temperature dependences of the elastic moduli and the Debye temperature.