Magnetic Properties of Nanocrystalline Co/Ti and Co/Zr Multilayers

It is shown that the Co sublayers grow in the soft magnetic nanocrystalline phase up to a critical thickness d≈3 and 2.8 nm for Co/Ti and Co/Zr MLs, respectively. The rapid decrease in the interlayer exchange coupling could be explained by its strong damping due to formation of a non-magnetic quasi-amorphous Co-Ti and Co-Zr alloy layer at the interfaces. The nanocrystalline 2.2 nm-Co/2 nm-Ti ML shows a weak 90° coupling near the transition zone from ferromagnetic to zero coupling

Magnetisation of Co/Ti Multilayers

We studied experimentally and theoretically the magnetisation of the Co/Ti multilayers. The results showed that the magnetic moments on Co atoms located at the Co-Ti interface are strongly reduced. For d$\text{}_{Ti}$=0.35 nm the estimated effective non-magnetic Co thickness at the Co-Ti interface amounts ≈ 0.08 nm and ≈ 0.1 nm at 4 K and 295 K, respectively. We found a good agreement between experimentally determined and theoretically calculated magnetisations

Magnetic domains studies in strongly and weakly exchange coupled Co/NiO bilayers

Results of the Auger electron spectroscopy measurements with depth profiling showed that at the Co-NiO interface only oxygen is present, making it very likely that only NiO is formed and no other nickel or cobalt compounds, which grow apparently with smaller probability. It has been also found that the average exchange coupling energy for the Co-NiO interface strongly depends on the preparation conditions. For the Co layers with strong interface exchange coupling, we have observed large uniform domains and 180° walls. On the other hand, the Co layers with the weak interface coupling showed large domains with a strong ripple structure and non-uniform 180° walls

Interlayer Exchange Coupling and Proximity Effect in V-Fe Multilayers

We have studied interlayer exchange coupling (IEC) in (110) oriented V/Fe multilayers with ultrathin sublayers up to 7 monolayers (ML). Results showed that IEC energy depends on both vanadium and iron layer thicknesses. The local maxima of the antiferromagnetic coupling were found for V(7 ML)/Fe(4 ML) and V(3 ML)/Fe(3 ML) multilayers (MLs). The strongest AFM coupling energy of about 1.0 mJ/m² was measured at 5 K for the V(7 ML)/Fe(4 ML) multilayer. The position of the AFM peak for V(X ML)/Fe(3 ML) MLs near 3 ML of V spacer was also revealed by ab-initio calculations. Furthermore, theoretical calculations show an induced negative magnetic moment on V atoms near the V-Fe and Fe-V interfaces due to the proximity effect