Peak effect in superconductors: melting of Larkin domains
NEC Research Institute, 4 Independence Way, Princeton,
NJ 08540, USA
2 Department of Physics, Princeton University, Princeton, NJ 08544, USA
Accepted: 12 July 1996
Motivated by the recent observations of the peak effect in high-Tc YBCO superconductors, we re-examine the origin of this unusual phenomenon. We propose that the sharp peak in the critical current as a function of temperature or magnetic field is an interesting manifestation of vortex-lattice melting in the presence of weak random pinning. Specifically, the rise of the critical current with increasing temperature or field is a result of a crossover from the Larkin pinning length to a length scale set by thermal fluctuations.
PACS: 74.60.Jg – Critical currents / 74.60.Ge – Flux pinning, flux creep, and flux-line lattice dynamics / 64.70.Dv – Solid-liquid transitions
© EDP Sciences, 1996