Influence of alloying on the electron momentum density in the Cu-Ni system

Abstract

We report on the measurement of the three-dimensional electron momentum density (EMD) of a 22 nm Cu/22 nm Ni sandwich foil and of a ${\mathrm{Cu}}_{0.50}{\mathrm{Ni}}_{0.50}$ alloy film with the same thickness, which was obtained from an identical sandwich by interdiffusion. The EMD's were measured by coincident detection of a Compton scattered photon with its recoil electron. The experiments were performed at the High-Energy beamline of the European Synchrotron Radiation Facility. The experimentally observed small change of the EMD due to alloying is reproduced by the Korringa-Kohn-Rostoker coherent-potential approximation scheme [Benedek et al., Phys. Rev. B 32, 7650 (1985)].