Magnetic and structural properties of Fe/Cu multilayers

Fe/Cu multilayers with Fe and Cu layers of equal thicknesses were grown by high-vacuum evaporation on Si(1 1 1) substrates at room temperature. The crystal orientation, the thickness of the elemental layers and the interplanar distances were analysed by both low- and high-angle X-ray di!raction in the }2 con"guration. The magnetic properties of Fe/Cu multilayers were studied by both a static and a dynamic technique, namely surface magneto-optical Kerr e!ect (SMOKE) and Brillouin light scattering (BLS). Longitudinal SMOKEcycles permitted us to determine the orientation of the easy axis of the magnetization and to put in evidence an appreciable in-plane magnetic anisotropy in multilayers with low periodicity and highly coherent structure. Polar loops were then used to determine the out-of-plane anisotropy "elds, showing that both "rst- and second-order contributions are to be considered in order to reproduce the hysteresis cycle. BLS was then exploited to detect thermaly excited spin waves through inelastic scattering of light. The out-of-plane anisotropy "elds evaluated by this high-frequency dynamic technique compare fairly well with the "rst-order values obtained by analysis of polar SMOKE hysteresis cycles