Local magnetization measurements on 100 nm type-II superconducting Pb thin films show that flux penetration changes qualitatively with temperature. Small flux jumps at the lowest temperatures gradually increase in size, then disappear near T = 0.7Tc. Comparison with other experiments suggests that the avalanches correspond to dendritic flux protrusions. Reproducibility of the first flux jumps in a decreasing magnetic field indicates a role for defect structure in determining avalanches. We also find a temperature-independent final magnetization after flux jumps, analogous to the angle of repose of a sandpile.
@article{arxiv.cond-mat/0307092,
title = {Vortex microavalanches in superconducting Pb thin films},
author = {H. A. Radovan and R. J. Zieve},
journal= {arXiv preprint arXiv:cond-mat/0307092},
year = {2009}
}