Comparative study of vortex pinning and creep in superconductors

N. HABERKORN; S. A. BAILY; B. MAIOROV; T. G. HOLESINGER; Q. X. JIA; H. ZHOU; T. TAJIMA; L. CIVALE

Washington

Conferencia; Applied Superconductivity Conference 2010; 2010

Lawrence Berkeley National Laboratory

Although the introduction of defects in HTS to improve vortex pinning has been extensively explored, the present knowledge of the structure-properties correlations is incomplete. Vortex dynamics depends on both intrinsic superconducting parameters, such as Tc, critical fields, anisotropy and the single- or multi-band character, and on the extrinsic effects produced by the interactions of vortices with the pinning energy landscape generated by the material microstructure. To gain a more general understanding of vortex matter, which is a topic of both fundamental and technological relevance, we have performed comparative studies of pinning and creep phenomena in a variety of type-II superconductors.We have studied thin films and single crystals of oxide HTS, pnictides, MgB2 and conventional low Tc superconductors. The materials were selected to cover a large spectrum of electronic anisotropies as well as single and double band examples. They also span several orders of magnitude in the critical current density Jc and in the fraction Jc/J0, where J0 is the depairing current density, as well as in the Ginzburg number (Gi) that measures the influence of the thermal fluctuations.