Testing the limits for critical currents in YBa$_{2}$Cu$_{3}$O$_{7}$ films

ORAL

Abstract

Vortex pinning in YBa$_{2}$Cu$_{3}$O$_{7}$ films can be very strong. At low temperatures and in the absence of applied magnetic field (\textbf{H}), critical current densities J$_{c}$ of about 20{\%} of the depairing limit have been obtained. This is as high as the best achieved in commercial Nb-based superconducting wires after decades of optimization. Remarkably, similar J$_{c}$s are attained in YBa$_{2}$Cu$_{3}$O$_{7}$ films grown by various methods that produce vastly different nanostructures, suggesting that perhaps we are close to an effective J$_{c}$ limit regardless of the details of the pinning mechanisms. In contrast, the different types of pinning centers (either naturally occurring or artificially introduced by material nanoengineering) produce distinctively different J$_{c}$ behavior as a function of \textbf{H} strength and orientation. I will present a comparison of pinning mechanisms in YBa$_{2}$Cu$_{3}$O$_{7}$ films and will analyze the possibilities of further improvements.

–

Authors

  • L. Civale

    • Superconductivity Technology Center, LANL, Los Alamos, NM
    • MPA-STC, LANL, Los Alamos, NM 87544

  • B. Maiorov

    • Superconductivity Technology Center, LANL, Los Alamos, NM
    • MPA-STC, LANL, Los Alamos, NM 87544

  • Scott Baily

    • National High Magnetic Field Laboratory, Los Alamos National Laboratory
    • Superconductivity Technology Center, LANL, Los Alamos, NM

  • Honghui Zhou

    • Superconductivity Technology Center, LANL, Los Alamos, NM

  • Frank Hunte

    • Superconductivity Technology Center, LANL, Los Alamos, NM

  • Igor Usov

    • Superconductivity Technology Center, LANL, Los Alamos, NM

  • Stephen Foltyn

    • Superconductivity Technology Center, LANL, Los Alamos, NM

  • Terry Holesinger

    • Superconductivity Technology Center, LANL, Los Alamos, NM

  • Quanxi Jia

    • Superconductivity Technology Center, MPA, Los Alamos National Laboratory, Los Alamos, NM
    • Superconductivity Technology Center, Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, NM 87545
    • Superconductivity Technology Center, LANL, Los Alamos, NM

  • Judith MacManus-Driscoll

    • Dept. of Materials Science, University of Cambridge, UK

  • Haiyan Wang

    • Texas A \& M University, College Station, TX