Eur. Phys. J. B 61, 391-396 (2008)
https://doi.org/10.1140/epjb/e2008-00090-4

Influence of non-uniform J_c distributions on flux jumps in high-temperature superconductors

Key Laboratory of Mechanics on Western Disaster and Environment, and Department of Mechanics and Engineering Science, College of Civil Engineering and Mechanics, Lanzhou University, Lanzhou, Gansu, 730000, China

Corresponding author: ^a zhouyh@lzu.edu.cn

Received: 29 October 2007
Revised: 6 December 2007
Published online: 5 March 2008

Abstract

The influence of non-uniform J_c distributions on flux jumps in high-temperature superconductors is investigated with the simplified models in the form of a composite superconducting slab consisting of different pinning regions. The magnetization loops and flux jumps for the simplified models are calculated with the modified recursion formulas which could predict the flux-jump fields. The valid ranges of the temperature and sweep rate for B_fj1 are specified and the fields of the subsequent jumps after the first flux jump of the inhomogeneous models are obviously lower than that of the homogeneous models. The results indicate that flux jump instability could be stimulated by non-uniform J_c distributions and with the increase of the discrepancy of J_c between different pinning regions the instability also increase.