Transition from disorder to order in thin metallic films studied with angle-resolved photoelectron spectroscopy.

The transition from disorder to order in Ag film grown on Au(111) was investigated by monitoring the quantum well states using angle-resolved photoelectron spectroscopy. Our results show that the binding energies do not alter, but the in-plane dispersion alters from flat to parabolic when the film is annealed. We suggest that there are isolated and ordered patches scattered across the film at an early stage of the transition and that atoms inside the patches are fully ordered along the surface normal. These ordered patches grow and merge together as the annealing temperature increases.