Long-range magnetoelectricity in type-II multiferroic NiI <sub>2</sub>
Abstract
Type-II multiferroics, where spin order induces ferroelectricity, exhibit strong magnetoelectric coupling. However, for the typical 2D type-II multiferroic NiI 2 , the underlying magnetoelectric mechanism remains unclear. Here, applying generalized spin-current model, together with first-principles calculations and a tight-binding approach, we build a comprehensive magnetoelectric model for spin-induced polarization. Such model reveals that third-nearest-neighbor spin pairs provide an unexpectedly strong contribution to the electric polarization, which rivals that of the first-nearest neighbors. Adopting such model, both experimental-detectable bound charge induced by spin-induced polarization at the spiral domain boundary, as well as polar vortex lattice induced by magnetic skyrmion lattice under moderate magnetic field, are predicted. Furthermore, by analyzing the orbital-resolved contributions to polarization, our tight-binding model reveals that the long-range magnetoelectric coupling is enabled by the strong e g - p hopping of NiI 2 . These findings can guide the identification and design of strongly magnetoelectric multiferroics.
Article Details
Journal Info
Proceedings of the National Academy of Sciences
National Academy of Sciences
Authors (13)
Weiyi Pan
Department of Physics, State Key Laboratory of Low Dimensional Quantum Physics, Tsinghua University
Zefeng Chen
Department of Physics, Key Laboratory of Computational Physical Sciences (Ministry of Education), Institute of Computational Physical Sciences, State Key Laboratory of Surface Physics, Fudan University
Tianxing Jiang
Department of Physics, Key Laboratory of Computational Physical Sciences (Ministry of Education), Institute of Computational Physical Sciences, State Key Laboratory of Surface Physics, Fudan University
Haitao Wang
Department of Central Laboratory, College & Hospital of Stomatology, Anhui Provincial Key Laboratory of Oral Diseases Research, Anhui Medical University
Dezhao Wu
Department of Physics, State Key Laboratory of Low Dimensional Quantum Physics, Tsinghua University
Weiqin Zhu
Department of Physics, Key Laboratory of Computational Physical Sciences (Ministry of Education), Institute of Computational Physical Sciences, State Key Laboratory of Surface Physics, Fudan University
Zhiming Xu
Department of Neurosurgery, Shanghai Sixth People’s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine
Lianchuang Li
Department of Physics, Key Laboratory of Computational Physical Sciences (Ministry of Education), Institute of Computational Physical Sciences, State Key Laboratory of Surface Physics, Fudan University
Junsheng Feng
School of Physics and Materials Engineering, Hefei Normal University
Tong Zhang
Bing-Lin Gu
Department of Physics, State Key Laboratory of Low Dimensional Quantum Physics, Tsinghua University
Wenhui Duan
State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics
Changsong Xu
Department of Physics, Key Laboratory of Computational Physical Sciences (Ministry of Education), Institute of Computational Physical Sciences, State Key Laboratory of Surface Physics, Fudan University