Thermal conductivity properties of glass-ceramic (Bi sub(2- delta - gamma )Ga sub( delta )Tl sub( gamma )) Sr sub(2)Ca sub(2)Cu sub(3)O sub(10+x) High-T sub(c) superconductors

摘要

Glass-ceramic BSCCO superconductors with nominal (Bi sub(2- delta - gamma )Ga sub( delta )Tl sub( gamma )) Sr sub(2)Ca sub(2)Cu sub(3)O sub(10+x) compositions, where delta identical with 0.20, 0.40, 0.60 and gamma identical with 0.10, 0.30, 0.40, have been prepared by the melt quenching method. The thermal conductivity Kappa (T) measurements were performed between 30K and 285K and results obtained found to be between 3.1 and 9.9 mW/cm. K depending on the substitution levels and temperature. Results obtained showed that the phonon-defect scattering dominates above the T sub(c) for all samples but below the T sub(c) a strong coupling mechanism occurs. The best electrical performance was obtained to be 113K and 107K for T sub(c) and T sub(zero) respectively.