Fermi-surface properties of alpha-phase alloys of copper with zinc

We consider the Fermi-surface properties of the $\alpha -{\mathrm{Cu}}_{1-c}{\mathrm{Zn}}_c$ system over the composition range $0\le c\le 0.3$. Our calculations are based on the application of the self-consistent coherent potential approximation to the muffin-tin Hamiltonian. The predictions of the theory with respect to the radii $k_{\mathrm{neck}}$, $k_{100}$, and $k_{110}$, and the size and shape of the alloy Fermi surface in several planes in the Brillouin zone are in good agreement with the available positron annihilation measurements and with the predictions of the rigid-band model. We discuss how the hitherto unmeasured disorder smearing of the alloy Fermi surface may be amenable to a direct experimental determination in concentrated alloys. The dilute impurity limit is considered in detail. The computed changes in areas for several orbits are in good accord with the corresponding results of de Haas-van Alphen experiments. The predicted Dingle temperatures, however, agree with measurements only to within a factor of 2. It is hoped that the present work will encourage further measurements, especially of the disorder smearing of the Fermi surface in concentrated alloys.