Understanding the origin of the magnetic anisotropy in iron silicide amorphous alloys

Summary form only given, as follows. Magnetic anisotropies in iron silicide amorphous alloys, produced in the form of thin films, can be induced either by applying an external field during the thin film deposition, or by oblique angle of incidence of the evaporated beam with respect to the normal to the substrate. The total effect of the two possible mechanisms depends on the concentration of Si in the film. This dependence was observed by applying a magnetic field during film deposition in the direction perpendicular to the anisotropy induced by the oblique incidence angle. The easy axis flipped from being parallel to the applied field to being perpendicular to it with increased Si concentration. The plot of the anisotropy energy vs. Si concentration showed a minimum at the transition point where the effect of both mechanisms was comparable. X-ray magnetic circular dichroism spectroscopy performed in these amorphous alloys showed that the orbital component of the magnetic moment was correlated with the anisotropy energy of the amorphous films. The orbital moment to spin moment ratio was higher than in bcc Fe.