INDUCTION OF SUPERCONDUCTIVITY IN PULSED-LASER ABLATED LA2CUO4 THIN-FILMS BY POSTDEPOSITION FLUORINATION

Pulsed laser ablation has been used to fabricate La2CuO4 thin films. S uperconducting properties have been successfully induced in the films by an ex-situ, post-ablation annealing process in F-2 gas resulting in a T-c (onset) of 36 K. The presence of two slightly different c-axis expanded phases in the X-ray diffraction data of the fluorinated films implies a degree of inhomogeneity in F-2 uptake. Critical current den sities (J(c)) and the irreversibility line have been established from hysteresis cycles. A J(c) of similar to 10(6) A cm(-2) for a typical f ilm was observed at 10 K in zero field.