Critical current density improved by laser-irradiation on growing surface in YBa2Cu3Ox superconducting films

Superconducting YBa 2 Cu 3 O x films with c -axis orientation on (100) MgO substrates were prepared by pulsed laser ablation with pulsed laser irradiation onto the growing film surface. The irradiation gives rise to a -axis-oriented crystallites in c -axis-oriented matrix, short c -axis length and smooth surface morphology without degradation in crystallinity of c -axis-oriented crystal. Critical current density J c of the film is improved by the laser irradiation, resulting in 2.6x10 6 A/cm 2 at 77 K and zero field, which is twice that of the non-irradiated one. In addition, an enhanced pinning effect was also observed at a high field.