Fabrication and Characterization of YBCO Thin Film Co-doped with BYNO + LAO Nanoparticles

Abstract

This study aims to enhance the critical current density (Jc) of a YBa2Cu3O7-x (YBCO) film by adding more pinning centers and reducing defects. Perovskite nanomaterials with positive and negative mismatch lattices with respect to YBCO were simultaneously doped on a YBCO film using a low-fluorine metal organic deposition technique. The co-doping with both positive and negative mismatch dopant was revealed to be effective at up to 10%, as compared with the previously reported amount for single nanoparticles (i.e., 7%). At doping levels of 8 mol% Ba2YNbO6 (positively mismatch perovskite) and 2 mol% LaAlO3 (negatively mismatch perovskite), the surface of the film was observed to be flat and dense with an improved critical current density and pinning force. The positive and negative mismatched lattice eliminated the long-range strains and introduced crystal defects; thus, the pinning centers became more effective. This study describes a feasible approach regarding the positive-negative mismatch theory by providing an optimal design for the effective pinning centers of a YBCO film. This approach can open a gateway for advanced applications of second-generation high-temperature coated conductors at the industrial level.