Thermal conductivity, thermal diffusivity and thermoelectric power of Sm-based bulk superconductors

The ab-plane thermal conductivity κab(T), thermal diffusivity αab(T) and thermoelectric power Sab(T) were measured for the highly-oriented Ag-doped superconducting materials Sm1+2xBa2+xCu3+xO7+5x (X = 0.1 ∼ 0.4) prepared by a melt process. The absolute value of κab and its characteristic enhancement below Tc were suppressed with increasing content X of the Sm2BaCuO5 (Sm211) secondary phase, while they were enhanced with increasing content of doped-Ag. The application of the magnetic field up to 10 T clarified that the phonon scattering by vortices was most enhanced with the applied field perpendicular to the ab-plane. The trapped magnetic field also seriously suppressed the κab(T) enhancement