EuO/Tb-Fe-Co EXCHANGE COUPLED FILMS

Abstract

~ Macroscopic ferrimagnets have been prepared by codepositing Co I Tb and EU 2 0 3 bye-beam evaporation. The films show compensation temperatures at compositions which indicate that the europium is in the divalent state and is coupled antiparallel to the Co magnetization. Under the present conditions of deposition, these films do not show perpendicular easy axis anisotropy, whereas previously studied Co-EuS films did. At room temperature there is magneto-optical evidence that the EuO precipitate phase is coupled antiparallel to the cobalt. That is, a film with 80 mole % Co (in the Co dominated composition range) shows a positive peak in the Kerr spectrum at 1.7 eV, whereas a Tb doped EuO film shows a negative peak in the same energy range. The change of sign of the Kerr peak shows that the EuO phase is coupled antiparallel to the cobalt.