Thermal annealing of the torn vortex lattice in ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7}$ crystals

Thermal annealing of the torn vortex lattice in ${YBa}_{2} {Cu}_{3} O_{7}$ crystals

G. Pasquini and V. Bekeris

Phys. Rev. B 71, 014510 – Published 14 January 2005

Abstract

We report evidence that the ac driven solid vortex lattice in YBCO single crystals reorganizes and accesses to robust configurations with different effective pinning potential wells arising in response to different system histories. The curvature of the pinning wells was determined by measuring the real ac penetration depth in the linear regime with a sensitive ac susceptometer. The stability of the different static configurations without assistance of macroscopic forces was also investigated. We find that they have distinct characteristic relaxation times which may be related to elastic or plastic creep processes.