Vortex avalanches in a type II superconductor
Résumé
We report on a study of the spatiotemporal variation of magnetic induction in a superconducting niobium sample during a slow sweep of external magnetic field. A sizable fraction of the increase in the local vortex population occurs in abrupt jumps. We compare the size distribution of these avalanches with the predictions of self-organized-criticality models for vortex dynamics.