Self-organized long-period adatom strings on stepped metal surfaces: Scanning tunneling microscopy,<i>ab initio</i>calculations, and kinetic Monte Carlo simulations

Abstract

Combined experimental and ab initio studies show that the surface-state-mediated adatom-step and adatom-adatom interactions are the driving forces for the self-organization of Fe adatoms on vicinal Cu(111) surfaces at low temperatures. Our scanning tunneling microscope observations and the kinetic Monte Carlo simulations reveal the self-organization of Fe adatoms into atomic strings. The interatomic separation $(1.2\phantom{\rule{0.3em}{0ex}}\mathrm{nm})$ in the strings is not determined by the nearest-neighbor distance $(0.26\phantom{\rule{0.3em}{0ex}}\mathrm{nm})$ of the Cu atoms along the step edge but by the wavelength of the surface-state charge density oscillations.