Flux quanta driven by high-density currents in low-impurity V3Si and LuNi2B2C: Free flux flow and fluxon-core size effect

TitleFlux quanta driven by high-density currents in low-impurity V3Si and LuNi2B2C: Free flux flow and fluxon-core size effect
Publication TypeJournal Article
Year of Publication2009
AuthorsGapud AA, Moraes S, Khadka RP, Favreau P, Henderson C, Canfield PC, Kogan VG, Reyes AP, Lumata LL, Christen DK, Thompson JR
Journal TitlePhysical Review B
Volume80
Pages134524
Date Published10/01
ISBN Number1098-0121
Accession NumberISI:000271351300103
Keywordsii superconductors, line-lattice transition, magnetoresistance, symmetry, vortex lattice
Abstract

High-density direct currents are used to drive flux quanta via the Lorentz force toward a highly ordered "free flux flow" (FFF) dynamic state, made possible by the weak-pinning environment of high-quality, single-crystal samples of two low-T-c superconducting compounds, V3Si and LuNi2B2C. We report the effect of the magnetic field-dependent fluxon-core size on flux flow resistivity rho(f). Much progress has been made in minimizing the technical challenges associated with the use of high currents. Attainment of a FFF phase is indicated by the saturation at highest currents of flux flow dissipation levels that are well below the normal-state resistance and have field-dependent values. The field dependence of the corresponding rho(f) is shown to be consistent with a prediction based on a model for the decrease of fluxon-core size at higher fields in weak-coupling BCS s-wave materials.

URL<Go to ISI>://000271351300103
DOI10.1103/Physrevb.80.134524