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arXiv · 1112.0978

Charge order in LuFe2O4: an unlikely route to ferroelectricity

J. de Groot·T. Mueller·R. A. Rosenberg·D. J. Keavney·Z. Islam·J. -W. Kim·M. Angst
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Abstract

We present the refinement of the crystal structure of charge-ordered LuFe2O4, based on single-crystal x-ray diffraction data. The arrangement of the different Fe-valence states, determined with bond-valence-sum analysis, corresponds to a stacking of charged Fe bilayers, in contrast to the polar bilayers previously suggested. This arrangement is supported by an analysis of x-ray magnetic circular dichroism spectra, which also evidences a strong charge-spin coupling. The non-polar bilayers are inconsistent with charge order based ferroelectricity.

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J. de Groot, T. Mueller, R. A. Rosenberg, D. J. Keavney, Z. Islam, J. -W. Kim, M. Angst. 2012-05-03. Charge order in LuFe2O4: an unlikely route to ferroelectricity. https://doi.org/10.1103/physrevlett.108.187601

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