Flux pinning in MOD YBCO films by chemical doping

Abstract

A novel nanomaterial synthesis technique has been developed to introduce 0D (particles),1D (columnar defects) and 3D (domains) nanoscale pinning centres in MODY1Ba2Cu3O7 (YBCO) coated conductors. We have succeeded in introducing nanoscale Y enriched particles, nanoscale90° rotated Y1/3Sm2/3Ba2Cu3O7 domains and nanoscale Zr enriched columnar defects into YBCOlayers by different chemical doping. The pinning force density inY2O3-doped YBCO film is found to be larger than that of pure YBCO film atall fields. Also it was found that YBCO films with Sm substituting for Yhave yielded improved critical current density characteristics over a widerange of magnetic fields. Maximum pinning force densities exceeding 7 and8 GN m−3 are obtained in 5% BZO-doped and Sm substituted YBCO films, respectively. Additionally,TEM studies revealed nanoscale Zr enriched columnar defects distributing in the matrix of thec-oriented YBCO film throughout the whole cross section. This indicates that chemicaldoping is a promising fabrication technique to create specific pinning landscapes in YBCOcoated conductors.