Enhanced flux pinning and critical currents in YBa2Cu3O7-δ films by nanoparticle surface decoration:: Extension to coated conductor templates

Interfacial engineering via nanoparticle substrate surface decoration has been extended to coated conductor templates. Preformed BaTiO3 and BaZrO3 nanoparticles were applied to substrate surfaces, prior to YBa2Cu3O7-delta (YBCO) deposition, by using a scalable and inexpensive technique of solution-based suspension. Compared to untreated reference samples, nanodecoration yields improved in-field critical current density (J(c)) as well as strong correlated pinning along the c-axis direction of the YBCO film. Accordingly, a much reduced falloff of J(c) with magnetic field strength was observed in all of the modified samples. In addition, scaling behavior of the normalized volume pinning force density (F-p) with respect to temperature provided insight as to the differences in flux pinning mechanisms dependent on the decoration technique. Finally, with these results our earlier proof-of-concept demonstrations on nanoparticle modified single crystal substrates were replicated on technological substrates, pointing to the versatility of this simple technique for realization of enhanced high temperature superconductor performance. (C) 2008 American Institute of Physics.