Time resolved nanosecond vortex dynamics in high Tc superconducting films

Abstract

Flux dynamics in a high Tc superconducting thin film is investigated in the ns time scale. The initial metastable state is determined by applying a pulsed magnetic field to a sample previous cooled below the irreversibility line. Selective local heating of the film with a pulsed laser spot lowers the vortex pinning force suddenly. The magnetic flux rearrangements that follow generate a voltage pulse between two contacts on the zero current biased sample. Detail simulations were performed in the framework of a phenomenological model based on Maxwell Equations with constitutive relations for creep and flux flow that fully describe the observed voltage signals. © 2003 Elsevier Ltd. All rights reserved.