Electronic Specific Heat in Dilute Alloys

Abstract

<p>The electronic part of the specific heat γ is calculated for dilute alloys at zero temperature. Only alloys where the impurity and the host ions have the same valence are considered. We take into account two mechanisms which change the value of γ of the pure metal. First the impurities affect the band structure and therefore the Fermi level density of states α (Eғ). Second they also influence the electron-phonon interaction and hence the mass renormalization. We calculate γ from first principles using the Born-von Karman lattice dynamics theory, electron-ion pseudopotentials and phonon Green's functions. The various corrections to γ are evaluated for NaK and KNa using the Ashcroft pseudopotentials form factors. It is found that the change in the mass renormalization is more important than that in α (Eғ) in calculating the electronic specific heat for the alloy.</p>