Enhanced Pinning Properties of the Bilayers of YDy0.5Ba2Cu3O7−δ by SrZrO3 Nanoparticles through Low Fluorine Metallorganic Solution Deposition

Abstract

Bilayered YDy0.5Ba2Cu3.6O7−δ superconducting films with a thickness of about 1 μ were deposited by metallorganic deposition method, an interlayer of secondary phase of SrZrO3 (SZO) and BaZrO3 (BZO) were inserted. Detailed growth mechanism studies of these structures as well as superconducting properties in different temperatures and magnetic field range (0–5 T) were investigated. Structural analysis showed that bilayer structure changed clearly the growth mechanism of YBCO. The SZO interlayer smoothens the film surface. Magnetic measurements of superconducting properties demonstrated that the critical temperature decreases slightly when both of SZO and BZO interlayer were inserted. This indicates a growing strain effect at the layer interfaces. The critical current densities as well as pining forces of bilayered YDy0.5Ba2Cu3.6O7−δ in the entire applied temperature and magnetic field range were enhanced by the insertion of SZO layer and decreased when BZO layer is introduced. The enhancement of the pinning properties is explained by the dense flux pinning in layered YDyBCO superconductors; this result may give further improvements in the current-carrying capability.