IOP Publishing, Superconductor Science and Technology, 5(12), p. L1-L4
DOI: 10.1088/0953-2048/12/5/101
Full text: Unavailable
A simple, low-cost and easily scalable method - thermal spray followed by post-spray annealing - has been successfully demonstrated for fabricating high-Jc epitaxial superconducting films of Tl0.5Pb0.5Sr1.6Ba0.4Ca2Cu3O9 [(Tl, Pb)-1223]. The process was performed by spraying a stoichiometric solution containing Tl, Pb, Sr, Ba, Ca and Cu nitrates onto LaAlO3 substrates heated to 300-400 °C. Subsequently, the amorphous films were placed inside a silver containment along with two semicircular unfired pellets, and were reacted and crystallized by a thermal anneal at 870 °C in air. X-ray diffraction showed that the films consist mainly of c-axis aligned (Tl, Pb)-1223 phase with a small amount of (Tl, Pb)-1212 phase. X-ray -scans revealed very good epitaxial growth. Four-probe transport measurements on a 4 mm wide and 1.2 µm thick film showed a superconducting transition temperature of 106-109 K, with a zero-field critical current of 51 A at 77 K, which corresponds to a critical current density of 1.1 × 106 A cm-2.