Ultra-high flux pinning properties of BaMO₃-doped YBa₂Cu₃O_7−<i>x</i>thin films (M = Zr, Sn)

Abstract

We studied the flux pinning properties of BaZrO3-doped YBa2Cu3O7−x and BaSnO3-doped YBa2Cu3O7−x films. We found that BaSnO3-doped films showed very high global pinning forces, Fp, of 28.3 GN m−3 (77 K, ) and 103 GN m−3 (65 K, ), twice that of BaZrO3-doped films. Transmission electron microscopy analysis showed that, in both films, nanorods of the dopant phase were incorporated. The BaSnO3 nanorods were nearly straight but the BaZrO3 nanorods became curved with the increasing film thickness.