Enhanced Flux-Pinning in Dy-Doped, MOD YBCO Films on RABiTS

Significant enhancements in flux-pinning were obtained for Dy-doped, YBCO films via a metalorganic deposition (MOD) process on rolling-assisted biaxially textured substrates (RABiTS). It has been reported previously that incorporation of excess rare-earth ions during the MOD process, results in improvement of J_c for H//c, however, a decrease in J_c for H//ab is observed. We report here that by altering the processing conditions the reduction in the magnitude of the current peak for H//ab can be minimized while significantly enhancing the random pinning at all field orientations. The result is a YBCO film with significantly reduced anisotropy compared to the typical YBCO films prepared by the MOD process. This is accomplished by incorporating both a high density of stacking faults and (Dy, Y)₂O₃ nanoparticles which result in the strong pinning for H//ab and a broad pinning peak for H//c respectively.