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 degrees 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 degrees walls.