A study on the thermoelectric power and thermal conductivity properties of the Y 1− xNd xBa 2Cu 3O 7− δ system

Abstract

Y 1− x Nd x Ba 2Cu 3O 7− δ ( x = 0.0–1.0) samples were prepared by solid-state reaction method. X-ray diffraction analysis and SEM investigation were used for structural characterization of the materials obtained. The Nd substitution into the YBaCuO system leads to decrease in the superconducting transition temperature and the zero resistance temperature. The influence of Nd substitution on thermoelectric properties of materials prepared was investigated. The thermoelectric power values of all the samples were obtained to be positive. It was found that the carrier concentration and Fermi energy level decreased with increasing the Nd concentration. A linear temperature dependence in the thermal conductivity down to the superconducting transition temperature and then a sharp rise just below the superconducting transition temperature was obtained. The thermal conductivity magnitude was suppressed by substitution of Nd which indicates the quasiparticles scattering on the Nd containing defects.