Dendritic Growth of Co/Cu Nanostructures on Stepped Cu(111) Surface

Self-learning kinetic Monte Carlo simulations are applied to simulate the growth of Co–Cu protrusions near step edges on a Cu(111) substrate at various temperatures, deposition fluxes, and relative concentrations. The shape of the dendritic protrusions depends on the relative concentration of the Co atom. The dependence of the fractal dimension of Co–Cu protrusions on the relative concentration of Co atoms can be monotonic or nonmonotonic, depending on temperature. The protrusions have Co backbones, whose fractal dimension differs from the fractal dimension of the entire Co–Cu protrusion.