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arXiv · 0905.4824

Spin-lattice coupling, frustration and magnetic order in multiferroic RMnO3

X. Fabreges·S. Petit·I. Mirebeau·S. Pailhes·L. Pinsard·A. Forget·M. T. Fernandez-Diaz·F. Porcher
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Abstract

We have performed high resolution neutron diffraction and inelastic neutron scattering experiments in the frustrated multiferroic hexagonal compounds RMnO3 (R=Ho, Yb, Sc, Y), which provide evidence of a strong magneto-elastic coupling in the the whole family. We can correlate the atomic positions, the type of magnetic structure and the nature of the spin waves whatever the R ion and temperature. The key parameter is the position of the Mn ions in the unit cell with respect to a critical threshold of 1/3, which determines the sign of the coupling between Mn triangular planes.

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X. Fabreges, S. Petit, I. Mirebeau, S. Pailhes, L. Pinsard, A. Forget, M. T. Fernandez-Diaz, F. Porcher. 2009-05-29. Spin-lattice coupling, frustration and magnetic order in multiferroic RMnO3. https://arxiv.org/abs/0905.4824

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