Interplay between chemical and magnetic roughness of Pt in a Pt/Co bilayer investigated with X-ray resonant magnetic reflectometry

The magnetization depth profiles of Pt have been investigated by X-ray resonant magnetic reflectivity measurements of sputtered Pt/Co bilayer systems with different chemical roughness values at the Pt/Co interface. The asymmetry ratio as a function of the angle of incidence has been measured at the Pt L3 near-edge absorption region at the maximum of the X-ray magnetic circular dichroism effect. The observed asymmetry ratios in the order of 0.5% are described quantitatively on the basis of a magnetically modified optical approach. The curves of the extracted magnetization profiles in the Pt layer show a different behavior corresponding to chemical roughness, while the magnetic saturation moment of Pt at the Pt/Co interface remains unaltered.