Growth of TlBa/sub 2/CaCu/sub 2/O/sub 7/ thin films using a controlled Tl-oxide source during processing

TlBa/sub 2/CaCu/sub 2/O/sub 7/ superconducting films 5000-6000 /spl Aring/ thick have been grown on LaAlO/sub 3/(100) substrates using oxide precursors in a two-zone thallination furnace. Smooth, nearly phase-pure 1212 films are reported, with transition temperature (T/sub c/)/spl sim/87 K, and low-magnetic field critical current densities J/sub c/(5 K)/spl sim/1/spl times/10/sup 7/ and J/sub c/(40 K)/spl sim/2-10/sup 6/ A/cm/sup 2/.<
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