Combined effect of a single grain boundary and artificial pinning centers on the critical current density in a YBa₂Cu₃O _7-δ thin film

The combined effect of a single grain boundary and artificial pinning centers (APCs) on the critical current density (Jc) in Y Ba2 Cu3 O7-δ thin films was investigated. The authors decorated the surface of a 5°-tilt bicrystal SrTi O3 substrate with Y2 O3 nanoislands to introduce APCs into the film. Jc of the bicrystal Y Ba2 Cu3 O7-δ film with APCs was measured in various magnetic fields. The APCs improved Jc in high magnetic fields, but not in low magnetic fields due to the existence of the grain boundary. The limiting mechanism of Jc in the bicrystal film containing APCs is discussed based on the experimental results.