Induced Spin Polarization in the Au Layers of Fe/Au Multilayer in an Antiparallel Alignment State of Fe Magnetizations by Resonant X-ray Magnetic Scattering at the Au L^sub 3^ Absorption Edge

A double periodic Fe1/Au/Fe2/Au multilayer with different Fe thicknesses was epitaxially grown on the MgO(001) substrate to investigate the magnetic structure of the Au spin polarization in an antiparallel alignment state of the Fe magnetizations. The establishment of the antiparallel alignment state at zero applied field was confirmed from the comparison of the magnetization curve measurement and simulation in the applied field along the [110] direction of the MgO substrate. Existence of the Au spin polarization orthogonal to the applied magnetic field was confirmed with resonant X-ray magnetic scattering (RXMS) measurements near the Au L3 absorption edge. Analysis of the RXMS pattern indicated that the magnetic depth profile of the spin polarization in the interior region of the Au layer was approximated to a square-wave shape, which suggests a ferromagnetic nature of the Au spin polarization sandwiched by the Fe layers.