ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
The thermodynamical stability of a superconducting La-326 compound, La1.8Sr0.2CaCu2O6, was studied by observing the phase formation at high pressures and decomposition at high temperatures. The superconducting La-326 compound, which was synthesized by means of an oxygen hot isostatic press annealing was found to be stable up to 800 °C at ambient pressure. When post-annealed at temperatures between 600 and 800 °C, the amount of superconductive volume fraction was increased and TcR=0 was also enhanced. When post-annealed at temperatures higher than 800 °C, La-326 started to decompose and the amount of secondary 214(T-structure) phase increased. It was confirmed that high-pressure annealing at an oxygen pressure of 10 atm was required to form the superconducting La-326 phase, which exhibits Tc of higher than 40 K. The high-pressure annealing conditions, such as Ar-to-oxygen ratio and annealing temperature, were optimized in order to make the La-326 phase superconductive. It was concluded that an oxygen pressure of at least 10 atm was required to "superconductor-ize'' the La-326 phase, regardless of the magnitude of total pressure.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.354094
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