Enhanced flux-pinning in fluorine-free MOD YBCO films by chemical doping

Abstract

YBCO films without and with dilute cobalt and zinc doping were prepared on (00l) LaAlO3 substrate by non-fluorine metal organic deposition method. Effects of dilute cobalt and zinc doping on biaxial texture, microstructure and flux-pinning properties of YBCO films were investigated. The surface density and smoothness of the doped YBCO films have been distinctly improved compared with that of the pure film. Dilute cobalt- and zinc-doped YBCO films exhibit significantly enhanced Jc values in the magnetic field. The best result is achieved in the cobalt-doped YBCO film. At 77K, Jc values of cobalt-doped film are 1.7 and 5.4 times higher than that of pure film in 0.5T and 1.5T, respectively. These results strongly suggest that dilute cobalt and zinc doping is a promising way to increase the current carrying capability of YBCO films.