The thermoelectric powers and resistivities of amorphous transition metal alloys

Abstract

The authors present experimental results for the resistivities, the temperature and magnetic field dependencies of the resistivity, and the thermopower of a number of Cu-Zr, Cu-Ti, Ni-Zr and Ni-Nb alloys together with a Cu50Zr40Fe10 alloy in the temperature range 4.2-270K. They show how the observed temperature dependence of the thermopowers may be understood in terms of electron-phonon enhancement. The resistivities and thermopowers of these systems are then calculated in the Ziman and Mott models and the authors show that neither model gives the correct resistivities, but that the Mott model gives reasonable agreement with the thermopowers. Surveying the published thermopower results they then find that none of them seem in conflict with Mott's s-d scattering model. The paper concluded with a discussion of the effects of hybridisation and of d band conduction in which the authors indicate how this agreement with the Mott formula may be retained in a more physically sound theory. In an appendix the general features of the Ziman and Mott models are illustrated by rough calculations of the resistivities and thermopowers of the liquid 3d transition metals.