Enhanced flux pinning in pulsed laser deposited Y Ba2Cu3O7−δ : BaTiO3 nanocomposite thin films

The effect of incorporation of BaTiO3(BTO) nanoparticles on the flux pinning properties of pulsed laser deposited YBCO:BTO thin films was studied. Substantial increase in the critical current density ( J C ) and the pinning force density ( F p ) of the nanocomposite thin films was observed. At 77 K, and zero applied magnetic field, the value of J C for YBCO and YBCO:BTO (2%) thin films were 2.93 MA/cm2 and 6.43 MA/cm2, respectively. At the same temperature and an applied magnetic field of 4 T, the value of J C increases from 3.6×104 A/cm2 for YBCO thin film to 2.7×105 A/cm2 for YBCO:BTO (2%) nanocomposite thin film. The study of temperature and field dependence of J C of YBCO and YBCO:BTO thin films indicates similar type of pinning. The lattice mismatch between YBCO and BTO seems to introduce more defects resulting in the improvement of flux pinning properties.