The electrical resistivity of potassium has been measured with high accuracy between 4.2 and 1.1 K. At temperatures above 2 K the dominant term is of the form $T{\mathrm{e}}^{-\frac{\theta }{T}}$, with $\theta =19.9\mathrm{}\pm 0.2$ K, which is due to electron-phonon scattering under phonon-drag conditions. At temperatures below 2 K a weak dependence of the form $A{T}^s$ is dominant, where $s$ is between 1 and 2. Tentatively one could ascribe this term to electron-electron scattering.

• Received 11 August 1976

DOI:https://doi.org/10.1103/PhysRevLett.37.1574