title: How Pb-overlayer islands move fast enough to self-assemble on Pb-Cu surface alloys.
abstract: Low-energy electron microscopy reveals that two-dimensional, approximately 50 000 atom, Pb-overlayer and vacancy islands both have diffusion coefficients of 25.6+/-0.8 nm2/sec at 400 degrees C on Pb-Cu surface alloys. This high mobility, key to self-assembly in this system, results from the fast transport of Pb atoms on the surface alloy and of Cu through the Pb overlayer. A high Pb vacancy concentration, predicted by ab initio calculations, facilitates the latter.
authors.affiliation: Sandia National Laboratories, Albuquerque, New Mexico 87185, USA.
authors.forename: M L
authors.initials: ML
authors.lastname: Anderson
authors.forename: N C
authors.initials: NC
authors.lastname: Bartelt
authors.forename: P J
authors.initials: PJ
authors.lastname: Feibelman
authors.forename: B S
authors.initials: BS
authors.lastname: Swartzentruber
authors.forename: G L
authors.initials: GL
authors.lastname: Kellogg