title: The crucial role of Mn spiral spin order in stabilizing the Dy-Mn exchange striction in multiferroic DyMnO3.
abstract: DyMnO3hosts the less addressed duality of multiferroicity, owing to the Dy-Mn exchange striction and inverse Dzyaloshinskii-Moriya interaction between Mn spin pairs. Although the duality in DyMnO3has been discussed earlier, there remains a question whether the Mn magnetic sublattice is necessarily multiferroic for generating the Dy-Mn exchange striction. In this work, we investigate the multiferroicity of Dy(Mn1-xFex)O3(0 ≤ x ≤ 0.1) through detailed magnetic and ferroelectric characterization. It is found that Fe-doping continuously suppresses the independent Dy spin order but instead promotes the Dy-Mn(Fe) coupling. This coupling benefits the Dy-Mn(Fe) exchange striction which remarkably enhances the ferroelectric polarization at a low doping level (x ≤ 0.015), beyond which the Mn spiral spin order breaks down leading to collapse of the macroscopic polarization at x ≥ 0.05. This work discloses the crucial role of Mn spiral spin order in stabilizing the Dy-Mn exchange striction and thus highlights the duality of multiferroicity in DyMnO3.
authors.affiliation: School of Physics & Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, China. jfwang@hust.edu.cn cllu@mail.hust.edu.cn.
authors.forename: H W
authors.initials: HW
authors.lastname: Wang
authors.affiliation: School of Physics & Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, China. jfwang@hust.edu.cn cllu@mail.hust.edu.cn.
authors.forename: C L
authors.initials: CL
authors.lastname: Li
authors.affiliation: School of Physics & Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, China. jfwang@hust.edu.cn cllu@mail.hust.edu.cn.
authors.forename: S L
authors.initials: SL
authors.lastname: Yuan
authors.affiliation: School of Physics & Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, China. jfwang@hust.edu.cn cllu@mail.hust.edu.cn.
authors.forename: J F
authors.initials: JF
authors.lastname: Wang
authors.affiliation: School of Physics & Wuhan National High Magnetic Field Center, Huazhong University of Science and Technology, Wuhan 430074, China. jfwang@hust.edu.cn cllu@mail.hust.edu.cn.
authors.forename: C L
authors.identifier: http://orcid.org/0000-0002-7314-5708
authors.initials: CL
authors.lastname: Lu
authors.affiliation: Laboratory of Solid State Microstructures and Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
authors.forename: J-M
authors.initials: JM
authors.lastname: Liu