TITLE:
Phase Transition in Superconducting Thin Films of Tl System Employing a One-Zone Furnace and Deposited by Spray Pyrolysis
AUTHORS:
Jorge Luis Rosas-Mendoza, L. Perez-Arrieta, Miguel Aguilar-Frutis, Ciro Falcony, R. Vázquez-Arreguín, Alejandro Miguel Rosas-Mendoza
KEYWORDS:
Superconductors; Thin Films; Ultrasonic Spray Pyrolysis
JOURNAL NAME:
Materials Sciences and Applications,
Vol.4 No.11,
November
26,
2013
ABSTRACT: A study of the phase transitions in superconducting thin films of the Thallium-Barium-Calcium-Copper (TBCCO) system is carried out. In particular, it was got the Tl-1223 phase. For this purpose, and using the ultrasonic spray pyrolysis technique, Barium-Calcium-Copper precursor films were first obtained. Upon deposition of the precursor films, and as a second step, they were thallium (Tl) diffused in the one-zone furnace at 860°C. This methodology resulted in superconducting films that showed a phase transition as follows: Tl-2223 → Tl-2223 + Tl-2212 → Tl-2212 → Tl-1223, achieved between 2 and 7 hours of thallium diffusion. The evidence of the phase transitions was corroborated by the experimental results of X-ray diffraction, energy dispersive spectroscopy and resistance-temperature measurements.