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

Article

关键词: LINE-LATTICE TRANSITION;    II SUPERCONDUCTORS;    VORTEX LATTICE;    MAGNETORESISTANCE;    SYMMETRY;   

DOI  :  10.1103/PhysRevB.80.134524

来源: SCIE

【 摘 要 】

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.

【 授权许可】

Free