INCORPORATION OF HYPERFINE PROBES INTO THE THIN-FILM SUPERCONDUCTOR YBA2CU3O7-DELTA DURING DEPOSITION

Radioactive In-111 has been incorporated into oriented thin films of Y Ba2Cu3O7-delta during a thermal coevaporation process. The hyperfine t echnique of perturbed gammagamma-angular correlation spectroscopy show s that 60% of the indium substitutes at a single site in the supercond uctor. We obtain spectra with reasonable statistics from 2 mCi of star ting material, about 1% of which is incorporated into the film. Other methods of incorporating indium into films and bulk YBa2Cu3O7-delta ha ve often resulted in a significant amount of indium being incorporated into impurity phases.