Influence of Au and Cu overlayers on the magnetic structure of Co films on W(110)

The dependence of the angular distribution of the magnetization in ultrathin epitaxial Co layers upon the thickness of Au and Cu overlayers is studied in situ by spin-polarized low-energy electron microscopy in the thickness range from 0 to 3 monolayers. Only Cu overlayers cause a peak in the coverage dependence of the perpendicular magnetic anisotropy at 1.5 ML coverage. The relation between the nanostructure of the over-layers and the anisotropy is discussed. [S0163-1829(99)01501-5].