VORTEX PINNING IN YBA2CU3O7-X FILMS

Citation
Dg. Xenikos et Tr. Lemberger, VORTEX PINNING IN YBA2CU3O7-X FILMS, Czechoslovak journal of Physics, 46, 1996, pp. 1653-1654
Citations number
11
Categorie Soggetti
Physics
ISSN journal
00114626
Volume
46
Year of publication
1996
Supplement
3
Pages
1653 - 1654
Database
ISI
SICI code
0011-4626(1996)46:<1653:VPIYF>2.0.ZU;2-#
Abstract
Evidence that pinning on linear or planar defects dominates the vortex dynamics in YBa2Cu3O7-X (YBCO) films is provided by complex impedance measurements at temperature 8 K < T < T-c and magnetic field 0<B<6 T. Below the vortex lattice melting transition B-g(T) but above a thresh old field B-p approximate to 8(1-T/T-c) T, the inductance of vortices increases as B-2, much less rapidly than predicted for collective pinn ing of vortices by point defects. Above the vortex melting line, criti cal scaling persists over the region B-g(T) < B < B(T) where the vort ex correlation length xi exceeds a characteristic length scale xi = x i(B=B) approximate to 450 Angstrom. The value of xi* is not sensitive to Al-doping in the Cu sites in the lattice and is close to the size of twin domains in the film. The nature of the observed crossovers is discussed in terms of available theoretical models for a glass-liquid transition at B-g.