Superperiodicity In The Thermal Faceting Of Au(111) Vicinal Surfaces
Résumé
Using scanning tunneling microscopy and low energy electron diffraction, the thermal faceting of two Au(111) vicinal surfaces belonging to the [011] zone is investigated. Above 700 K, a final stable state is found: it consists of a periodic succession of (111) and (755) facets. The superperiod is 70 Angstrom for Au(1199) and 110 Angstrom for Au(433). The quantitative agreement between our results and the observations of macroscopic gold crystals strongly suggests that the novel periodic morphology is an equilibrium state. Possible origins to account for this morphology are discussed.