Ab initio study of microscopic processes in the growth of Co on Cu(001)

Using density-functional theory we investigate the energetics of various diffusion processes relevant for the heteroepitaxial growth of Co on Cu(001). We focus on how the barrier height depends on the local coordination, the interaction with the substrate and spin-polarization. We determine the temperature at which the different atomistic processes are activated and discuss their implications for the growth morphology. In particular, atomic exchange divides the temperature scale into two distinct regions: At lower temperatures growth proceeds similar to the homoepitaxial case, above the activation temperature of exchange a qualitatively different bimodal surface morphology evolves. PACS 68.55.-a; 68.36.Fx; 75.70.Rf; 68.47.De; 71.15.Mb