Observation of a surface state on Cu₃Au(111)

The authors observe a peak close to the Fermi level in the photoelectron spectrum of both ordered and disordered Cu 3 Au(111) near normal emission. They have studied this feature as a function of photon incidence angle, emission angle and photon energy, and conclude that it is due to a surface state whose character is similar to those previously observed on Cu(111) and Au(111).