Time resolved nanosecond vortex dynamics in high Tc superconducting films

HERNAN FERRARI; DAVID IBACETA; VICTORIA BEKERIS; ESTEBAN CALZETTA; LUIS CORRERA

CRYOGENICS

Elsevier

Lugar: Amsterdam; Año: 2004 vol. 44 p. 29 - 35

0011-2275

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.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.2003 Elsevier Ltd. All rights reserved. Keywords: Flux pinning; Flux creep; Vortex dynamics; Critical currentsFlux pinning; Flux creep; Vortex dynamics; Critical currents