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arXiv · 0802.0604

Order Parameters and Phase Diagram of Multiferroic RMn$_2$O$_5$

A. B. Harris·Amnon Aharony·Ora Entin-Wohlman
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Abstract

The generic magnetic phase diagram of multiferroic RMn$_2$O$_5$ (with R=Y, Ho, Tb, Er, Tm), which allows different sequences of ordered magnetic structures for different R's and different control parameters, is described using order parameters which explicitly incorporate the magnetic symmetry. A phenomenological magneto-electric coupling is used to explain why some of these magnetic phases are also ferroelectric. Several new experiments, which can test this theory, are proposed.

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A. B. Harris, Amnon Aharony, Ora Entin-Wohlman. 2008-06-06. Order Parameters and Phase Diagram of Multiferroic RMn$_2$O$_5$. https://doi.org/10.1103/physrevlett.100.217202

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