Thermoelectric power of Pr 2−yCe yCuO 4−ò superconductors with various content of Ce

Abstract

The temperature dependence of the thermoelectric power (TEP) of superconducting ceramic Pr 2−yCe yCuO 4−ò samples with various Ce content (0.13 < y < 0.17) has been investigated. The TEP value is small and has a weak temperature dependence within the range of 80–300 K. With increase in Ce content the TEP sign reverses from negative to positive. The comparison of the data obtained with TEP of La 2−xSr xCuO 4−ò compound points to the significantly less value of both the effective mass of carriers and the density of their states in Pr 2−yCe yCuO 4−ò. The Emery model for HTSC explains satisfactorily the experimental data for Pr 2−yCe yCuO 4−ò and La 2−xSr xCuO 4−ò and gives the correct sign and the order of TEP and effective mass value in these compounds.