Observation of a Bulklike Fermi Surface for a Monolayer of Ni on Cu(001)

We find that the photoelectron angular distributions from the Fermi surface of a monolayer Ni film on Cu are identical to those from thick Ni films and single-crystal Ni(001), and agree well with theoretical predictions for bulk Ni. This bulklike behavior in the monolayer film is attributed to the short screening length of electrons in metals, the similarity of the Ni and Cu cores, and a hybridization between Ni and Cu facilitating an interaction with the underlying crystal field.