Structure and magnetism of self-organized Co islands

This investigation turns its attention to magnetic effects of cobalt islands on a non-magnetic substrate. The preparation technique of MBE enables the creation of hat and well-ordered surfaces of hcp-Co(0001) if the evaporation onto a W(110) crystal is carried out at ambient temperatures. Subsequent heating to about 1000 K causes a phase transition from thin films to islands. The investigations are carried out in VUV photoemission with polarized synchrotron radiation, LEED and Scanning Tunneling Microscopy (STM). We employ the technique of magnetic linear dichroism in the angular distribution of photoemission (MLDAD) from valence bands. The MLDAD effect shows significant differences between a fiat cobalt layer and cobalt islands. Variations due to the excitation energies are discussed with respect to a fully-relativistic bulk-band-structure calculation.