Hall effect, thermoelectric power and electrical conductivity measurements in vitreous CdGe x As2

Abstract

A series of measurements of Hall effect, thermoelectric power and electrical conductivity have been performed on the vitreous CdGe_xAs₂ having a Ge content of 0.2, 0.3, 0.4, 0.6 and 1 mol respectively. The electrical conductivity has an exponential behaviour in the temperature range 185–500 K only for the 0.6 and 1 mol composition. It deviates from the exponential behaviour at lower temperatures for the 0.2, 0.3 and 0.4 compositions. The thermoelectric power is positive for CdGe_0.2As₂, negative for CdGe_0.6As₂ and CdGe_1.0As₂, whereas it changes sign for CdGe_0.3As₂ and CdGe_0.4As₂. The Hall coefficient is negative for alll compositions except for the CdGe_1.0As₂. The Hall mobilities differ widely for the different compositions and have the values of 1.5 × 10^–2 to 1.3 × 10^–1 cm² V^–1 s^–1 at room temperature.