Characterization of FePd bilayers and trilayers using soft x ray resonant magnetic scattering and micromagnetic modeling

We have studied bilayers and trilayers of FePd thin film alloys, where each of the constituting layers has a different magnetic anisotropy, as controlled by the growth conditions. The competition between the magnetocrystalline anisotropy and the shape anisotropy in these films leads to the formation of stripe domains with a period of 100 nm, which has been imaged by magnetic force microscopy MFM . The average magnetic anisotropy has been obtained from the in plane and perpendicular magnetic field dependence, measured using vibrating sample magnetometry VSM . We measured the soft x ray resonant magnetic scattering SXRMS at the Fe L3 edge using sigma linearly polarized light, which is sensitive to the magnetization profile in the layers. The magnetic configuration of the layer systems was modeled using micromagnetic software GL FFT, Copyright CNRS . The results of the micromagnetic modeling were used for a numerical simulation of the reflectivity scan and the magnetic rod scans of the SXRMS. This allowed us to determine parameters, such as the lateral roughness, the magnetic period, the magnetic correlation length, and the magnetic layer thickness. The good agreement obtained with the experimental results demonstrates that SXRMS provides in depth information that cannot be obtained from either MFM or VS