Temperature-Dependent Electrical Resistivity of Potassium below 2 K

Abstract

Recent measurements of the temperature-dependent electrical resistivity ${\ensuremath{\rho}}_{T}$ of potassium down to 1.1 K have indicated the presence of a possible new term $A{T}^{n}$, with $2>n>1$ and $A\ensuremath{\propto}{\ensuremath{\rho}}_{0}$, the residual resistivity. We have measured ${\ensuremath{\rho}}_{T}$ down to \ensuremath{\cong} 0.5 K in order to confirm the existence of this term and to examine it more closely. We indeed find $A\ensuremath{\propto}{\ensuremath{\rho}}_{0}$ and $n\ensuremath{\simeq}1.5$. We speculate that it arises from the electron-electron interaction modified by a size effect and possibly dislocation scattering.