STUDYING IN-SITU ON THE SUPERCONDUCTING TRANSITION AND INTERNAL FRICTION OF A HIGH Tc SUPERCONDUCTOR YBa2Cu307−δ

Abstract

The resistence, internal friction and modulus of a high Tc superconductor YBa2Cu3O7−δ were measured in-situ in 80–300 K. Two obvious peaks of internal friction were observed about Tc. On account of character of peaks, it is suggested that these two peaks are associated with the electronic relaxation between Cu3+ and Cu2+. The peak and anomalies of Young’s modulus observed in the range between 160 K and 280 K may be related to the adjustment of deficiency of oxygen.