Crystal Phases of BiSrCaCu2Ox Heat Treated in a Vacuum-Sealed System
- 1 August 1988
- journal article
- Published by IOP Publishing in Japanese Journal of Applied Physics
- Vol. 27 (8A) , L1429
- https://doi.org/10.1143/jjap.27.l1429
Abstract
Heat treatment in a vacuum-sealed system on BiSrCaCu2O x was studied in comparison with that in air. The melting temperature was lowered from 880°C in air to 850°C in the vacuum-sealed system. The formation of the phase with 37 Å c spacing was enhanced in the vacuum-sealed system by heating above the melting temperature and the subsequent annealing in air improved the sharpness of the superconducting transition at 110 K. The heat treatment in the reduced pressure also caused the reduction of the Cu ion and it was suggested that the oxidation state of the Cu ion played an important role in the formation of the phase with 37 Å c spacing.Keywords
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