Magnetic proximity effect in Co/Pt multilayers studied with X-ray Resonant Reflectivity.

A permanent magnetic moment can be found in $4d$ and $5d$ transition metals when interfaced with a ferromagnet. This magnetic proximity effect (MPE) is often linked to strong perpendicular magnetic anisotropy, as is the case of Co/Pt multilayers, attracting considerable interest for a number of technological applications. We employed X-ray magnetic circular dichroism and X-ray resonant reflectivity to investigate the depth profile of Co and Pt moments in a $(Co/Pt)_{4}$ multilayer. The goal of our work is to monitor the dependence of MPE along the growth direction of the multilayer and to correlate this information with the structural properties.