Imaging the Fermi Surface Through Diffuse Scattering from Concentrated Disordered Alloys

Abstract

We show qualitatively how the Fermi surface of a disordered alloy will be reflected in the local-order diffuse scattering of x rays, etc., through anomalies similar to those predicted by Kohn for phonon scattering. These ideas are then applied to the existing data on the splitting of the diffuse spots from Cu-Au alloys above $T_c$ and, more tentatively, to the scattering profile from $\beta -\mathrm{CuZn}$. The results indicate that disordered ${\mathrm{Cu}}_3$Au has a Fermi surface much like copper's while disordered Cu${\mathrm{Au}}_3$ resembles gold.