Critical current density enhancement in YBa2Cu3O6.8 films on buffered metallic substrates

Abstract
A transition buffer, consisting of subbuffers grown at different temperatures, was used to enhance the crystallinity and the transport properties of YBa2Cu3O6.8 (YBCO) films on metallic substrates. Films were fabricated using in situ laser deposition and were strongly c‐axis oriented. Critical temperature of 87 K and critical current density of 3×104 A/cm2 at 77 K were obtained for a 0.5‐μm‐thick YBCO film with a 0.2 μm transition yttrium‐ stabilized ZrO2 buffer layer. Also, the magnetic field dependence of Jc could be enhanced by using Pt‐coated metallic substrates.