Magnetic circularly polarized 2presonant photoemission of nickel

We report the observation of two resonance channels in the 2p resonant photoemission of ferromagnetic nickel using circularly polarized soft x rays. By identifying the local 3${\mathit{d}}^8$ and 3${\mathit{d}}^7$ configurations in the valence-band photoemission spectra, we are able to assign structures in 2p core-level-absorption and magnetic-circular-dichroism spectra to many-body 2${\mathit{p}}^5$3${\mathit{d}}^{10}$ and 2${\mathit{p}}^5$3${\mathit{d}}^9$ configurations as well as to a critical point in the band structure. The Ni data provide a critical test for theoretical models of x-ray absorption and magnetic-circular-dichroism spectroscopy of transition-metal magnetic materials. This work also demonstrates the unique possibilities provided by circularly polarized light for separating the Auger process from the resonant-photoemission process and unraveling the electronic structure.