SUPERCONDUCTING THALLIUM OXIDE-FILMS VIA AN ELECTRO-DEPOSITED PRECURSOR

Electro-deposited precursor films of BaCaCuO (BCCO) doped with Ag were prepared on Ag foil. The electrodeposited films were processed using a two-zone anneal, which employs a Tl source zone and a separate sample zone, both within an O2 ambient. The annealed films showed c-axis oriented 1223 as the major phase. At 77 K and no magnetic field, the critical current density was 4.42 x 10(4) A/cm2 using the field criterion of 1 muV/cm. The field dependence for the Tl-1223 film was equally impressive, showing 8.2 x 10(3) A/cm2 at 5.5 T (77 K) for the field oriented parallel to the ab plane (H(parallel-to) ab) and parallel to the applied current.