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arXiv · 1109.1328

General Theory for the Ferroelectric Polarization Induced by Spin-Spiral Order

H. J. Xiang·E. J. Kan·Y. Zhang·M. -H. Whangbo·X. G. Gong
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Abstract

The ferroelectric polarization of triangular-lattice antiferromagnets induced by helical spin-spiral order is not explained by any existing model of magnetic-order-driven ferroelectricity. We resolve this problem by developing a general theory for the ferroelectric polarization induced by spin-spiral order and then by evaluating the coefficients needed to specify the general theory on the basis of density functional calculations. Our theory correctly describes the ferroelectricity of triangular-lattice antiferromagnets driven by helical spin-spiral order, and incorporates known models of magnetic-order-driven ferroelectricity as special cases.

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H. J. Xiang, E. J. Kan, Y. Zhang, M. -H. Whangbo, X. G. Gong. 2011-09-07. General Theory for the Ferroelectric Polarization Induced by Spin-Spiral Order. https://doi.org/10.1103/physrevlett.107.157202

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