Electrical and thermal transport coefficients of pure vanadium

The electrical and thermal conductivities of high-purity vanadium samples have been measured over a wide range of low temperatures and analyzed in terms of electron-impurity scattering, electron-electron scattering, and electron-phonon interband and intraband scattering. In the normal state, electron-phonon interband scattering is a major factor over the entire temperature range, with the electron-phonon intraband scattering becoming important above 50 K. At lower temperatures, our results show evidence of electron-electron scattering. The thermal conductivity in the superconducting state was fit by Bardeen-Rickayzen-Tewordt theory, with $\frac{2\Delta \mathrm{}\left(0\right)\mathrm{}}{k_B{T}_c\simeq 3.386}$. The deviation of the experimental points from this fit at lower temperatures was used to obtain the lattice conductivity, providing additional information on the phonon-electron interaction and phonon-boundary scattering. The mass-enhancement factor, $\lambda$, is also calculated and found to be consistent with those values obtained from specific-heat and tunneling-effect measurements.