Theory of thermally activated vortex bundles flow over the directional-dependent potential barriers in type-II superocnductors

TL;DR

This paper develops a theoretical model for thermally activated vortex bundle flow in type-II superconductors, analyzing how directional-dependent energy barriers influence resistivity and vortex dynamics, with results aligning with experimental data.

Contribution

It introduces a new theoretical framework for vortex bundle flow considering directional-dependent barriers and calculates related resistivities, matching experimental observations.

Findings

Resistivities depend on temperature and magnetic field.

Flow velocity of vortex bundles is derived.

Results agree with experimental data.

Abstract

The thermally activated vortex bundle flow over the directional-dependent energy barrier in type-II superconductors is investigated. The coherent oscillation frequency and the mean direction of the random collective pinning force of the vortex bundles are evaluated by applying the random walk theorem. The thermally activated vortex bundle flow velocity is obtained.The temperature- and field-dependent Hall and longitudinal resistivities induced by the bundle flow for type-II superconducting bulk materials and thin films are calculated. All the results are in agreement with the experiments.