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Disentangling multipole resonances through a full x-ray polarization analysis

C. Mazzoli·S. B. Wilkins·S. Di Matteo·B. Detlefs·C. Detlefs·V. Scagnoli·L. Paolasini·P. Ghigna
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Abstract

Complete polarization analysis applied to resonant x-ray scattering at the Cr K-edge in K2CrO4 shows that incident linearly polarized x-rays can be converted into circularly polarized x-rays by diffraction at the Cr pre-edge (E = 5994 eV). The physical mechanism behind this phenomenon is a subtle interference effect between purely dipole (E1-E1) and purely quadrupole (E2-E2) transitions, leading to a phase shift between the respective scattering amplitudes. This effect may be exploited to disentangle two close-lying resonances that appear as a single peak in a conventional energy scan, in this way allowing to single out and identify the different multipole order parameters involved.

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C. Mazzoli, S. B. Wilkins, S. Di Matteo, B. Detlefs, C. Detlefs, V. Scagnoli, L. Paolasini, P. Ghigna. 2008-01-16. Disentangling multipole resonances through a full x-ray polarization analysis. https://doi.org/10.1103/physrevb.76.195118

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