Spin polarized neutron reflectivity study of a Co/Cu superlattice

We present spin polarized neutron reflectivity data on a Co/Cu(111) superlattice and show how not only the magnitude but also the orientation of the average magnetic moment of each layer can be extracted by analyzing the polarization of the reflected beam. This method allows more detailed conclusions about the exchange coupling of magnetic layers across nonmagnetic interlayers and the magnetic in-plane anisotropy in such systems. We present a theoretical fit to the spin-flip and non-spin-flip data which leads to quantitative conclusions about the spin structure. These spin polarized neutron reflectivity results coincide well with the macroscopic magnetic properties which were measured using the magneto-optic Kerr effect revealing a newly discovered uniaxial anisotropy in this system.