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arXiv · 1207.6913

Magnetic frustration, phase competition and the magneto-electric effect in NdFe3(BO3)4

J. E. Hamann-Borrero·S. Partzsch·S. Valencia·C. Mazzoli·J. Herrero-Martin·R. Feyerherm·E. Dudzik·C. Hess·A. Vasiliev·L. Bezmaternykh·B. Buechner·J. Geck
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Abstract

We present an element selective resonant magnetic x-ray scattering study of NdFe3(BO3)4 as a function of temperature and applied magnetic field. Our measurements show that the magnetic order of the Nd sublattice is induced by the Fe spin order. When a magnetic field is applied parallel to the hexagonal basal plane, the helicoidal spin order is suppressed and a collinear ordering, where the moments are forced to align in a direction perpendicular to the applied magnetic field, is stabilized. This result excludes a non-collinear spin order as the origin of the magnetically induced electric polarization in this compound. Instead our data imply that magnetic frustration results in a phase competition, which is the origin of the magneto-electric response.

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J. E. Hamann-Borrero, S. Partzsch, S. Valencia, C. Mazzoli, J. Herrero-Martin, R. Feyerherm, E. Dudzik, C. Hess, A. Vasiliev, L. Bezmaternykh, B. Buechner, J. Geck. 2012-07-30. Magnetic frustration, phase competition and the magneto-electric effect in NdFe3(BO3)4. https://doi.org/10.1103/physrevlett.109.267202

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