Current dependence of pinning energy and flux dynamics in high temperature superconductors

Attanasio C., Coccorese C., Maritato L., Salluzzo M., Salvato M., Prischepa S., ...More

IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY, vol.7, no.2, pp.1173-1176, 1997 (SCI-Expanded, Scopus) identifier identifier

  • Publication Type: Article / Article
  • Volume: 7 Issue: 2
  • Publication Date: 1997
  • Doi Number: 10.1109/77.620701
  • Journal Name: IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1173-1176
  • Karadeniz Technical University Affiliated: No

Abstract

We show that the usually observed logarithmic U(J) dependence at large magnetic fields is related to the increasing number of free flowing vortices distributed in the weak pinning centers, with respect to the vortices in the strong pinning centers in the flux creep regime. Increasing the flux density (i.e. increasing the external magnetic field) the flux distribution on the pinning centers has a larger dispersion (sigma u much greater than k(B)T) and this leads to a logarithmic U(J) behavior. The comparison with the experimental data seems to prove this idea.