Pinning enhancement of YBa2Cu3O7-d thin films with Y2BaCuO5 nanoparticulates

A comparison study is given of a typical superconducting YBa₂Cu₃O_7-d (Y123) film and a Y123 film containing a nonsuperconducting Y₂BaCuO₅ (Y211) phase nanoparticulate dispersion. The inclusion of the second phase nanoparticulates was for the express purpose of increasing superconducting film´s magnetic pinning strength with the resultant improved in-field critical current density. LaAlO₃ substrates were used and the Y123 and Y211 nanoparticulates were grown by pulsed laser deposition (PLD). The Y211 nanoparticulate dispersion in the Y123 resulted from multiple consecutive depositions by PLD of the respective targets. The Y123 phase maintained excellent epitaxy with high in-plane orientation with and without the Y211 inclusions. With the Y211 additions, the critical current densities of the films increased significantly in applied magnetic fields as compared to the high quality Y123 film with no Y211 additions.