MAGNETIC-PROPERTIES OF CO-NB/PD MULTILAYERED FILMS

Co-Nb/Pd multilayered films with amorphous Co-Nb layers were prepared by rf sputtering. Magnetic measurements showed that the Pd atoms near the Co-Nb layers are polarized by Co atoms. The total magnetically active thickness per bilayer contributed from the polarization of Pd atoms is about 3.2 angstrom. A perpendicular easy axis of films can be obtained when the Co-Nb layers are thinner than 7 angstrom. The interface anisotropy K(s) is about 0.25 erg/cm2. An oscillatory variation in saturation magnetization versus the thickness of the Pd layers with a period of about 10 angstrom is obtained. It is related to the structure changes in the Co or Pd layers. When the thickness of the Pd layers is around 14 angstrom, an antiferromagnetic polarization of Pd atoms is induced in the center of the Pd layers.