Determination of buried interface composition and magnetism profiles using standing-wave excited soft x-ray emission and inelastic scattering.

We demonstrate that a standing-wave/wedge (swedge) method for probing buried solid-solid interfaces can be carried out using soft x-ray emission spectroscopy (XES) and resonant inelastic x-ray scattering (RIXS). For the particular case of an Al₂O₃/Fe/Cr structure of relevance to giant magnetoresistance, measurements of Fe L and Cr L total intensities and Fe L magnetic circular dichroism are used to derive for both the top and bottom Fe interfaces the depth profile of composition and the depth dependence of the atom-specific Fe contribution to magnetization. Using XES and RIXS in this method, as compared to photoelectron spectroscopy in prior work, permits studying more deeply buried interfaces, and suggests future applications to a wide variety of magnetic and nonmagnetic nanostructures. [ABSTRACT FROM AUTHOR]