Abstract
Temperature and compositional dependences of magnetization of Fe100−XErX sputtered films (with 8<X<30) are analysed using the mean field theory, and the sublattice magnetic moments MFe and MEr are calculated as a function of composition. This analysis yields the effective exchange interaction between Fe–Fe and Fe–Er atom pairs. High-field magnetization studies performed at 4.2 K in magnetic fields up to 5.5 T on amorphous Fe100−XErX alloys have revealed, for samples with stoichiometry close to that of a compensated ferrimagnet, a magnetic behavior that is characteristic of a non-collinear magnetic structure of the Er and Fe sublattices. From the non-collinear regime the exchange interactions between the Fe and Er magnetic sublattices have been accurately evaluated.