Phonon drag and the low temperature electrical resistivity of the alkalis

Abstract

We derive an equation for the low temperature ideal electrical resistivity of an alkali metal. Our approach, unlike recent variational calculations, incorporates phonon drag in a consistent fashion and thus reveals the sensitivity of this effect to the details of the electron-phonon coupling. Although the magnitude of the resultant resistivity cannot be determined without detailed numerical calculations, an exponential temperature dependence at very low temperatures is very easily demonstrated.