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

Author

Attanasio, C. ; Coccorese, C. ; Maritato, L. ; Salluzzo, M. ; Salvato, M. ; Prischepa, S.L. ; Kushnir, V.N. ; Varilci, A.

Author_Institution

Dipartimento di Fisica, Salerno Univ., Italy

Volume

7

Issue

2

fYear

1997

fDate

6/1/1997 12:00:00 AM

Firstpage

1173

Lastpage

1176

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 (/spl sigma//sub u//spl Gt/k/sub B/T) and this leads to a logarithmic U(J) behavior. The comparison with the experimental data seems to prove this idea.

Keywords

critical current density (superconductivity); flux creep; flux pinning; high-temperature superconductors; current dependence; flux creep regime; flux density; flux dynamics; free flowing vortices; high temperature superconductors; large magnetic fields; larger dispersion; logarithmic U(J) dependence; pinning energy; weak pinning centers; Bismuth compounds; Creep; High temperature superconductors; Informatics; Magnetic field measurement; Magnetic fields; Shape; Superconducting transition temperature; Temperature dependence; Temperature distribution;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.620701

Filename

620701