Electromagnetic Properties of Thick Film REBCO Tapes

Abstract

RE-Ba-Cu-O (REBCO, RE = rare earth) coated conductors are characterized by an anisotropic pinning behavior in applied magnetic fields. Over the years, incorporation of BaZrO3 nanocolumns has been an effective approach to improve the pinning force and reduce the anisotropy in these materials. In this paper, the magnetic field dependence of critical current density (J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> ) of 4.7 μm thick films grown by advanced metal-organic chemical vapor deposition (A-MOCVD) with 5% and 15% Zr addition has been studied. At 65 K, 1.5 T, the 5% Zr-added thick films manifest a J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> at H||c-axis that surpasses 3 MA/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> . Increasing the Zr content to 15% results in a plateau in J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> from 0.4 to 6.5 T and enables higher values of J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> at fields above 6 T at 65 K. Tapes with 15% of added Zr exhibit a lift factor in critical current density (J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> (Temperature, Applied Magnetic Field) / J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> (77 K, 0 T)) exceeding 13 and a J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> exceeding 11 MA/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> at 30 K, 3 T.