Collective spin waves in Fe-Pd and Fe-W multilayer structures

Abstract

The complete, theoretically predicted band of collective magnetostatic spin-wave excitations has been observed for the first time in Fe-Pd and Fe-W multilayer structures by Brillouin scattering. Despite the large number of bilayers (49-90) discrete spin-wave modes due to a quantization of the momentum perpendicular to the stack have been observed in the upper half of the band. For Fe-Pd multilayer structures the saturation magnetization shows a monotonic decrease of up to 30% from that of the bulk Fe for modulation wavelengths down to 33 \AA{}A.