MAGNETIC-PROPERTIES OF ND FE DOUBLE-LAYERS GROWN ON SI(111) BY ELECTRON-BEAM EVAPORATION/

In-plane ferromagnetic resonance (FMR) has been used to study the room -temperature magnetic and crystalline properties of Nd/Fe bilayers. Se veral samples were grown by electron beam evaporation onto Si(111) sub strates, for various Fe and Nd thicknesses. The symmetry of the resona nce held as a function of the azimuthal angle departs from the sixfold one expected for a (111)Fe film. The FMR data were analyzed in the fr amework of a phenomenological model, which takes into account first- a nd second-order magnetocrystalline, uniaxial and perpendicular anisotr opies. Our analysis reveals that the deviation from the sixfold symmet ry is due to a combined effect of an induced uniaxial in-plane anisotr opy with a small misorientation of the substrate surface from the (111 ) plane. We suggest that the in-plane uniaxial anisotropy may originat e from an arrangement of (111) terraces separated by well oriented ato mic steps formed during the small miscut. The effect of the Nd overlay er is to induce a perpendicular anisotropy which is not sufficiently l arge to overcome the demagnetizing field and push the magnetization en tirely out-of-plane. (C) 1998 American Institute of Physics.