The epitaxial growth of BaSnO3 buffer layer on IBAD-MgO template and its effects on GdBa2Cu3O7−δ film: A preliminary study

We report a successful fabrication of c-axis oriented GdBa2Cu3O7−δ (GdBCO) films on the BaSnO3 (BSO) buffer layers on ion-beam assisted deposition (IBAD)-MgO template by pulsed-laser deposition (PLD). The (00l) growth and in-plane textures of BSO buffer layers were found sensitive to the substrate temperature (Ts). With increasing the BSO layer thickness up to ∼165nm, in-plane texture (Δϕ∼6.2°) of BSO layers was almost unaltered while completely c-axis oriented BSO layers were obtainable from samples with the thickness below ∼45nm. On the BSO buffer layers showing in-plane texture of 6.2° and RMS surface roughness of ∼8.6nm, GdBCO films were deposited at 780–800°C. All GdBCO films exhibited Δϕ values of 4.6–4.7°, Tc,zero of ∼91K, and critical current density (Jc) over 1MA/cm2 at 77K in a self-field. The highest Jc value of 1.82MA/cm2 (Ic of 51A/cm-width) was achieved from the GdBCO film deposited at Ts of 790°C. These results support that BSO can be a promising buffer layer on the IBAD-MgO template for obtaining high-Jc GdBCO coated conductors.