Soft X-ray Circular Reflectivity from Ferromagnetic Transition-Metal Films Near the Brewster's Angle: Theoretical and Numerical X-ray Resonant Magnetic Scattering Study

We first report a novel phenomenon that manifests itself in a colossal difference in soft x-ray reflectivity from ferromagnetic transition-metal films between the left- and right-handed circular polarization (LCP and RCP) modes at a resonance near normal Brewster’s angle. Theoretical and numerical studies of sft x-ray resonant magnetic scattering using the circular-polarization-mode basis reveal that this effect arises from a totally destructive interference of photons scattered individually from chargem orbital, and spin degrees of freedom in magnetized thin films that selectively occurs only for one helicity of the opposite circular modes when the required criteria are fulfilled. Across the normal Brewster’s angle. the polarization state of scattered soft x-ray is continuously variable from the RCP to the LCP mode (or vice versa) through the linear s polarization mode by changing the incidence angle of linear p-polarized x rays at the resonance.