Thermal conductivity and thermo-power of View the MathML source (View the MathML source and View the MathML source) bulk superconductors

In this paper, we present temperature dependent electrical conductivity ρ(T), thermal conductivity κ(T) and thermoelectric power S(T) for co-doped superconducting compounds Y 0.95Pr0.5Ba2(Cu1−xMx)3O7−δ(M=Fe,Mn,Zn and Ni). The XRD patterns confirm that all the samples are single phased. Pristine Y Ba2Cu3O7−δ depicts a pronounced hump-like structure in κ(T) below its transition temperature. With Pr-doping, a reduction in the peak height of the hump is observed. It is found that the hump structure is further suppressed with transition metal co-doping, and is viewed in terms of the phonon scattering with defect structure, electrons and phonons. S(T) data depicting a sign reversal with co-doping, has been analyzed in the framework of a narrow band model