Direct correlation of Cr 3d orbital polarization and O K-edge X-ray magnetic circular dichroism of epitaxial CrO2 films

The role of delocalization and hybridization in complex magnetic oxides has been investigated by magnetic oxygen K-edge absorption of circular polarized soft X-rays in epitaxial grown CrO2 as a function of the azimuthal angle at grazing incidence. Unusual strong variations in the typically small X-ray magnetic circular dichroism (XMCD) signal have been observed. Those angular dependencies of the typical CrO2 oxygen K-edge XMCD signal could be quantitatively interpreted in terms of an induced anisotropic Cr 3d orbital magnetism for different spectral regions of the unoccupied density of states. The results strongly suggest a delocalized non-ionic magnetic behavior of the conduction electrons.