title: General theory for the ferroelectric polarization induced by spin-spiral order.
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.
authors: Key Laboratory of Computational Physical Sciences (Ministry of Education) and Department of Physics, Fudan University, Shanghai 200433, People's Republic of China. hxiang@fudan.edu.cn
authors: H J
authors: HJ
authors: Xiang
authors: E J
authors: EJ
authors: Kan
authors: Y
authors: Y
authors: Zhang
authors: M-H
authors: MH
authors: Whangbo
authors: X G
authors: XG
authors: Gong