  By Monte Carlo simulations in the canonical ensemble, we have studied the
magnetic anisotropy in Fe/Dy amorphous multilayers. This work has been
motivated by experimental results which show a clear correlation between the
magnetic perpendicular anisotropy and the substrate temperature during
elaboration of the samples. Our aim is to relate macroscopic magnetic
properties of the multilayers to their structure, more precisely their
concentration profile. Our model is based on concentration dependent exchange
interactions and spin values, on random magnetic anisotropy and on the
existence of locally ordered clusters that leads to a perpendicular
magnetisation. Our results evidence that a compensation point occurs in the
case of an abrupt concentration profile. Moreover, an increase of the
noncollinearity of the atomic moments has been evidenced when the Dy anisotropy
constant value grows. We have also shown the existence of inhomogeneous
magnetisation profiles along the samples which are related to the concentration
profiles.
