Thermoelectric power of undoped and doped Y-Ba-Cu-O superconductor between 77 and 300K

Abstract

Temperature dependence of electrical resistivity and thermoelectric power of undoped Y-Ba-Cu-O sintered pellet and that doped with small amount of sulphur and silver are presented. While the nature of the temperature dependence of electrical resistivity and thermoelectric power remains similar, their absolute values are strongly influenced by the presence of the dopant. Thermoelectric power data for all the samples can be fitted to an expression of the type, S = AT +B/T. It is argued from the data that the precursor peak in thermoelectric power near T > Tc is of electronic origin due to superconducting fluctuations.