Mössbauer study of Fe/Ag multilayers on Cu(100)

Abstract Fe/Ag multilayers composed of ultrathin layers were grown on Cu(1 0 0) in ultrahigh vacuum by molecular beam epitaxy. Magnetic analysis of the Fe-layers (95% enriched in 57Fe) was performed by in situ conversion electron Mossbauer spectroscopy at room temperature and 100 K. Samples with different thicknesses of the Ag-spacers (2–3 monolayers) as well as with different thicknesses of the Fe-layers were prepared in order (a) to determine whether the magnetic orientation (in-plane/out of plane) of the 57Fe-layers is changed, (b) to study its influence on the intensity of the hyperfine magnetic field and (c) to identify superparamagnetism due to small Fe islands inside the layers.