Effect of mesoscopic relaxations on diffusion of Co adatoms on Cu(111)

Abstract

We demonstrate that mesoscopic relaxations in systems with low migration barriers significantly affect atomic motion in the vicinity of adsorbed islands. Atomic-scale calculations for Co islands and steps on Cu(111) reveal that adsorbate-induced strain in the substrate makes surface diffusion of Co adatom anisotropic. As the adatom approaches the island side, the migration barrier exhibits strong oscillations. Large energy barriers for the attachmnent of adatoms to islands are predicted by our calculations.