Fermi Surface of Disordered Cu3Au as Determined by Angle-resolved Photoemission

The bulk Fermi surface of the disordered phase of Cu3Au has been experimentally mapped using angle‐resolved constant initial‐state photoemission spectroscopy. The shape of the Fermi cross‐section so determined has been found to be well described by a rigid band model. Comparison with previously reported de Haas–van Alphen results of the ordered phase has shown that the neck radius is unaltered within experimental error. We find, however, that the Fermi surface belly radius of the disordered phase is ∽20–30% larger than the corresponding distance as determined by an LMTO calculation for the ordered material.