An angle-resolved photoemission study of single-crystal CuNi alloys

The author have measured the angle-resolved energy distributions of electrons photoemitted from the (100) faces of single crystals of pure Cu and Cu-5 at.% Ni. Cu-23 at.% Ni and Cu-40 at.% Ni random substitutional alloys, using various photon energies and incident directions. They interpret the richly structured data using first-principles calculations of the configurationally averaged photocurrent within the framework of the Korringa-Kohn-Rostoker coherent potential approximation (KKR CPA). The quantitative agreement found between theory and experiment shows that the KKR CPA can describe electron states in these alloys in k point by k point detail. They conclude that the electronic structure of Cu-Ni alloys consists, for the most part, of bands whose smearing in energy and wavevector is less than their separation.