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arXiv · 0807.3527

Charge order in LuFe2O4: antiferroelectric ground state and coupling to magnetism

M. Angst·R. P. Hermann·A. D. Christianson·M. D. Lumsden·C. Lee·M. -H. Whangbo·J. -W. Kim·P. J. Ryan·S. E. Nagler·W. Tian·R. Jin·B. C. Sales·D. Mandrus
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Abstract

X-ray scattering by multiferroic LuFe2O4 is reported. Below 320 K, superstructure reflections indicate an incommensurate charge order with propagation close to (1/3,1/3,3/2). The corresponding charge configuration, also found by electronic structure calculations as most stable, contains polar Fe/O double-layers with antiferroelectric stacking. Diffuse scattering at 360 K, with (1/3,1/3,0) propagation, indicates ferroelectric short-range correlations between neighboring double-layers. The temperature dependence of the incommensuration indicates that charge order and magnetism are coupled.

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M. Angst, R. P. Hermann, A. D. Christianson, M. D. Lumsden, C. Lee, M. -H. Whangbo, J. -W. Kim, P. J. Ryan, S. E. Nagler, W. Tian, R. Jin, B. C. Sales, D. Mandrus. 2008-10-22. Charge order in LuFe2O4: antiferroelectric ground state and coupling to magnetism. https://doi.org/10.1103/physrevlett.101.227601

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