Flux pinning distribution and E-J characteristics of 2G YBCO Tapes

11th European Conference on Applied Superconductivity

Falorio, Iole^1 ; Young, Edward A^1 ; Yang, Yifeng^1

Institute of Cryogenics, Faculty of Engineering and Environment, University of Southampton, SO17 1BJ, United Kingdom^1

关键词: Apparent power;    Critical current distribution;    E-J characteristics;    Flux-flow resistance;    Lower temperatures;    Pinning potential;    Power law behaviour;    Temperature range;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/507/2/022004/pdf
DOI  :  10.1088/1742-6596/507/2/022004

来源: IOP

【 摘 要 】

E-J characteristics of SuperPower YBCO 2G tapes have been measured in the temperature range 15K-80K. It was found that the E-J characteristics deviate significantly from the standard power-law behaviour with apparent power exponent decreasing continuously at high voltage with increasing current. The deviation of E-J characteristic from the standard power-law was found to be consistent with a Weibull distribution of critical current. The identical scaling of E-J characteristics above 40K suggests a common critical current distribution. At lower temperature the critical current distribution becomes narrower to give higher apparent power exponent at lower temperature. With the critical current distribution model it is shown that the dissipation can be correlated directly to the flux flow resistance of Bardeen. The distribution of the critical current can be associated with a distribution of pinning potential of collective pinning and the headline pinning range is obtained as function of temperature.