title: Demixing processes in AgPd superlattices.
abstract: The present scanning tunneling microscopy (STM) study describes the growth of silver-palladium heterostructures at room temperature, with ab initio simulations of ordered AgPd phases supporting the interpretation of STM images. First, the growth of Pd on an Ag(111) surface proceeds in a multilayer mode, leading to the formation of a columnar structure. Then, upon Ag deposition on this structure, Ag and Pd partially mix and form a two-dimensional AgPd alloy on top of the columns. Finally, an atomically flat Ag(111) surface is restored, and two-dimensional growth continues. An interpretation of this peculiar growth mode including interfacial alloying is proposed based on thermodynamic and kinetic arguments.
authors.affiliation: Laboratoire de Physique des Matériaux Electroniques (LPME), Facultés Universitaires Notre-Dame de la Paix, Namur, B-5000, Belgium.
authors.forename: J
authors.initials: J
authors.lastname: Dumont
authors.forename: R
authors.initials: R
authors.lastname: Sporken
authors.forename: M J
authors.initials: MJ
authors.lastname: Verstraete
authors.forename: J
authors.initials: J
authors.lastname: Ghijsen
authors.forename: X
authors.initials: X
authors.lastname: Gonze