Molecular dynamics and molecular static methods were used to study the effect of misfit dislocations upon adatom diffusion in close proximity to the dislocation core in heteroepitaxial systems, using many-body interaction potentials. The present system consisted of several layers (three–seven) of Cu on top of a Ni(111) substrate. The misfit dislocations were created with the core located at the interface between the Cu film and the Ni substrate, using the repulsive biased potential method described earlier. It was found that the presence of the defect under the surface strongly affected the adatom trajectory, creating an anisotropy in atomic diffusion, independent of the thickness of the Cu film. The potential energy surface available to the adatom was also calculated and the energy barriers for adatom diffusion in the proximity of the core region and on the defect-free surface were compared.

Effect of Misfit Dislocation on Surface Diffusion. M.Aminpour, O.Trushin, T.S.Rahman: Physical Review B, 2011, 84[3], 035455