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arXiv · 0809.1167

Determination of magnetic order of the rare-earth ions in multiferroic TbMn2O5

R. D. Johnson·S. R. Bland·C. Mazzoli·T. A. W. Beale·C. H. Du·C. Detlefs·S. B. Wilkins·P. D. Hatton
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Abstract

We have employed resonant x-ray magnetic scattering to specifically probe the magnetic order of the rare-earth ions in multiferroic $\mathrm{TbMn_2O_5}$. Two energy resonances were observed, one originated from the E1-E1 dipolar transition and the other from the E2-E2 quadrupolar transition. These resonances directly probe the valence 5d band and the partially occupied 4f band, respectively. First, full polarization analysis, which is a measurement of the scattered polarization as a function of incident polarization, confirmed a spin polarization of the terbium valence states (probed by the E1-E1 transition) by the $\mathrm{Mn^{4+}}$ spin density in the commensurate phase. Second, full polarization analysis data were collected in the low-temperature incommensurate and commensurate phases when tuned to the E2-E2 resonance. By employing a least-squares fitting procedure, the spin orientations of the terbium ion sublattice were refined.

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R. D. Johnson, S. R. Bland, C. Mazzoli, T. A. W. Beale, C. H. Du, C. Detlefs, S. B. Wilkins, P. D. Hatton. 2008-09-06. Determination of magnetic order of the rare-earth ions in multiferroic TbMn2O5. https://doi.org/10.1103/physrevb.78.104407

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