Current - voltage characteristics in magnetic field for layered superconductor with intrinsic pinning of Josephson vortices

RESUMO

The results of measurements of the transverse voltage in the Hall configuration, Uy, under conditions of motion of the charge and vortex subsystems in orhtogonal magnetic and electric fields on epitaxial films of the layered high-temperature superconductor Nd2-xCexCuO4 are presented. the motion of Josephson vortices across CuO2 layers (along the c-axis) is analyzed considering the effects of intrinsic pinning. An exponential dependence of critical depinning current jc(B) for Josephson vortices is established in contrast to the power law dependences for Abrikosov vortices. With increasing external magnetic field after the depinning by a magnetic field at B=Bc, the onset of the vortex creep regime, which evolves into the flux-flow regime at crossover field B=Bf, is observed.