The Open Superconductors Journal

2010, 2 : 12-18
Published online 2010 June 2. DOI: 10.2174/1876537801002010012
Publisher ID: TOSUPERJ-2-12

Theory of Thermally Activated Vortex Bundles Flow Over the Directional- Dependent Potential Barriers in Type-II Superconductors

Wei Yeu Chen
Department of Physics, Tamkang University, Tamsui 25137, Taiwan, China.

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 flow velocity of the vortex bundles is obtained self-consistently. 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. PACS: 74.25.Fy, 74.25.Qt, 74.72.-h.

Keywords:

Thermally activated bundle flow, directional-dependent potential barrier, vortex dynamics.