title: Strong K-edge magnetic circular dichroism observed in photon-in-photon-out spectroscopy.
abstract: A large enhancement of the x-ray magnetic circular dichroism is observed at the iron K absorption preedge of magnetite. This is achieved by performing resonant inelastic x-ray scattering (RIXS) experiments with a 2p hole in the final state of the second-order optical process. We measured and calculated the full 1s2p RIXS planes for opposite helicities of the incoming circularly polarized x rays. The crystal field multiplet calculations show that the enhancement arises from 2p-3d Coulomb repulsions and 2p and 3d spin-orbit coupling. The observed magnitude of the RIXS magnetic circular dichroism effect is ∼16%. This opens up new opportunities for a broad range of research fields allowing for truly bulk-sensitive, element-, and site-selective measurements of 3d transition metal magnetic moments and their ordering using hard x-ray photons.
authors.affiliation: Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, 30-059 Kraków, Poland. marcin.sikora@agh.edu.pl
authors.forename: Marcin
authors.initials: M
authors.lastname: Sikora
authors.forename: Amélie
authors.initials: A
authors.lastname: Juhin
authors.forename: Tsu-Chien
authors.initials: TC
authors.lastname: Weng
authors.forename: Philippe
authors.initials: P
authors.lastname: Sainctavit
authors.forename: Carsten
authors.initials: C
authors.lastname: Detlefs
authors.forename: Frank
authors.initials: F
authors.lastname: de Groot
authors.forename: Pieter
authors.initials: P
authors.lastname: Glatzel