Magnetic field dependence of critical current density in Sm/sub 1+x/Ba/sub 2-x/Cu/sub 3/O/sub 6+/spl delta// films prepared by pulsed laser deposition

We have investigated Sm/sub 1+x/Ba/sub 2-x/Cu/sub 3/O/sub 6+/spl delta// (SmBCO) films deposited by pulsed laser deposition technique using stoichiometric and Sm-rich SmBCO (x = 0.08) laser targets. In the SmBCO films deposited using the target of x = 0.08, the critical current density (J/sub c/) at 77 K with zero applied field was obtained 4.3 MA/cm/sup 2/ at film thickness of 1.1 /spl mu/m. To study the pinning mechanism of SmBCO films, we investigated the magnetic field (0 /spl sim/ 9 T) dependence of J/sub c/ for x = 0 and x = 0.08 films. From this result, we found the different behavior of the J/sub c/ between x = 0 and x = 0.08 films. We examined the difference of pinning mechanism from the scaling law and the microstructure of film using transmission electron microscopy.