Self-organized long-period adatom strings on stepped metal surfaces: Scanning tunneling microscopy,ab initiocalculations, and kinetic Monte Carlo simulations

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 (1.20.3em0exnm) in the strings is not determined by the nearest-neighbor distance (0.260.3em0exnm) of the Cu atoms along the step edge but by the wavelength of the surface-state charge density oscillations.