Theory of Magnetic-Field-Induced Polarization Flop in Spin-Spiral Multiferroics
arXiv:1511.07960 · doi:10.1103/PhysRevB.92.224412
Abstract
The magnetic-field-induced 90-degree flop of ferroelectric polarization P in a spin-spiral multiferroic material TbMnO3 is theoretically studied based on a microscopic spin model. We find that the direction of the P-flop or the choice of +Pa or -Pa after the flop is governed by magnetic torques produced by the applied magnetic field H acting on the Mn spins and thus is selected in a deterministic way, in contradistinction to the naively anticipated probabilistic flop. This mechanism resolves a puzzle of the previously reported memory effect in the P direction depending on the history of the magnetic-field sweep, and enables controlled switching of multiferroic domains by externally applied magnetic fields. Our Monte-Carlo analysis also uncovers that the magnetic structure in the P||a phase under H||b is not a so-far anticipated simple ab-plane spin cycloid but a conical spin structure.
7 pages, 4 figures, accepted for publication in Physical Review B
References in corpus (13)
- Spin current and magneto-electric effect in non-collinear magnets
- Role of the Dzyaloshinskii-Moriya interaction in multiferroic perovskites
- Multiferroics: different ways to combine magnetism and ferroelectricity
- Origin of electromagnon excitations in \textit{R}MnO
- Dynamics of Multiferroic Domain Wall in Spin-Cycloidal Ferroelectric DyMnO
- Spin model of magnetostrictions in multiferroic Mn perovskites
- Theory of electromagnon in the multiferroic Mn perovskites: Vital role of higher harmonic components of the spiral spin order
- Coupling of frustrated Ising spins to magnetic cycloid in multiferroic TbMnO3
- Theoretically predicted picosecond optical switching of spin chirality in multiferroics
- First-principles stabilization of an unconventional collinear magnetic ordering in distorted manganites
- Theory of magnetic switching of ferroelectricity in spiral magnets
- Field dependence of magnetic correlations through the polarization flop transition in multiferroic TbMnO3 : evidence for a magnetic memory effect
- Magnetic field induced dehybridization of the electromagnons in multiferroic TbMnO3