Atomic structure of Ni nanoclusters on Cu(001) surfaces

Depositions of Ni clusters on a Cu(001) surface have been simulated by molecular dynamics in order to produce magnetic nanostructures. Two arrangements of the atoms at the interface between the Ni clusters (a few monolayers) and the Cu substrate, overlapped and non-overlapped, have been analysed. The difference between Ni and Cu lattice parameters (2.6%) gives rise to strain at the interface, which is the cause of magnetoelastic anisotropy. We have focused our interest especially on matching effects. The bombardment energy was varied between 0 and 1 eV/atom. Differences in the nanocluster morphology due to this have been discussed. Lattice defects which develop in the deposited clusters have been analysed. Final atomic distances, especially mean changes in lattice parameters, have been quantified at the interface. A study of atomic mixing and of its influence in spacing between layers has been also accomplished.