Magnetic field orientation dependence of flux pinning in (Gd,Y)Ba2Cu3O7−x coated conductor with tilted lattice and nanostructures

The dependence of the critical current density (Jc) on the orientation of an applied magnetic field was studied for a prototype (Gd,Y)Ba2Cu3O7−x (GdYBCO) coated conductor fabricated by MOCVD on an IBAD-MgO template. Additional rare-earth cations (Y and Gd) and Zr were incorporated into the superconducting film to form (Y,Gd)2O3 and BaZrO3 nanoparticles extended nearly parallel to the a–b planes and to the c-axis, respectively, to enhance the flux pinning. In-field measurement of Jc was carried out with electrical current flowing either along or perpendicular to the longitudinal axis of the tape, while a maximum Lorentz force configuration was always maintained. Details in the angular dependence of Jc were related to the unique structure of the film, specifically the tilt in the GdYBCO lattice and the tilts in the extended (Y,Gd)2O3 and BaZrO3 nanoparticles. XRD and TEM were used to study the structure of the coated conductor. The effect of the misalignment between the external field H and the internal field B on the angular dependence of Jc is discussed.