Anisotropy and directional pinning in YBa_2Cu_3O_(7-x) with BaZrO_3 nanorods

摘要

Measurements of anisotropic transport properties (dc and high-frequency regime) of driven vortex matter in YBa_2Cu_3O_(7-x) with elongated strong-pinning sites (c-axis aligned, self-assembled BaZrO_3 nanorods) are used to demonstrate that the effective-mass angular scaling takes place only in intrinsic physical quantities (flux-flow resistivity), and not in pinning-related Labusch parameter and critical currents. Comparison of the dynamics at different time scales shows evidence for a transition of the vortex matter toward a Mott phase, driven by the presence of nanorods. The strong pinning in dc arises partially from a dynamic effect.