Multiferroicity induced by dislocated spin-density waves

Abstract

We uncover a new pathway towards multiferroicity, showing how magnetism can drive ferroelectricity without relying on inversion symmetry breaking of the magnetic ordering. Our free-energy analysis demonstrates that any commensurate spin-density-wave ordering with a phase dislocation, even if it is collinear, gives rise to an electric polarization. Due to the dislocation the electronic and magnetic and inversion centers do not coincide, which turns out to be a sufficient condition for multiferroic coupling. The novel mechanism explains the formation of multiferroic phases at the magnetic commensurability transitions, such as the ones observed in YMn${}_2$O${}_5$ and related compounds. We predict that in these multiferroics an oscillating electrical polarization is concomitant with the uniform polarization. On the basis of our theory we put forward new types of magnetic materials that are potentially ferroelectric.

4 pages, Phys. Rev. Letters, in press

References in corpus (7)

• Spin current and magneto-electric effect in non-collinear magnets
• Weak ferromagnetism and magnetoelectric coupling in bismuth ferrite
• Role of the Dzyaloshinskii-Moriya interaction in multiferroic perovskites
• Magnetically driven ferroelectric order in Ni${}_3$V${}_2$O${}_8$
• Ferroelectric polarization flop in a frustrated magnet MnWO${}_4$ induced by magnetic fields
• A New Multiferroic Material: MnWO4
• Structural Anomalies at the Magnetic and Ferroelectric Transitions in $RM{n}_2{O}_5$ (R=Tb, Dy, Ho)

Cited by in corpus (20)

• Erratum: Landau Analysis of the Symmetry of the Magnetic Structure and Magnetoelectric Interaction in Multiferroics [Phys. Rev. B 76, 05447 (2007)]
• Switching the Ferroelectric Polarization by External Magnetic Fields in the Spin = 1/2 Chain Cuprate LiCuVO4
• Optical coupling to spin waves in the cycloidal multiferroic BiFeO3
• New phase transition in $P{r}_{1-x}C{a}_{x}Mn{O}_3$ system: evidence for electrical polarization in charge ordered manganites
• Electronic correlations decimate the ferroelectric polarization of multiferroic HoMn2O5
• First-principles study of the lattice and electronic structures of TbMn${}_2$O${}_5$
• Non-resonant and Resonant X-ray Scattering Studies on Multiferroic TbMn2O5
• Complex Spin Structures and Origin of the Magneto-Electric Coupling in YMn2O5
• Microscopic mechanisms of spin-dependent electric polarization in 3d oxides
• Magnetic structure of the field-induced multiferroic GdFe3(BO3)4
• Spin amplitude modulation driven magnetoelectic coupling in the new multiferroic FeTe${}_2$O${}_5$Br
• An x-ray resonant diffraction study of multiferroic DyMn2O5
• Effect of Inversion Symmetry on Incommensurate Order in Multiferroic RMn2O5, R=rare earth
• The incommensurate magnetic structure of YMn2O5: a stringent test of the multiferroic mechanism
• Multiferroicity due to nonstoichiometry in the chain cuprate LiVCuO_4
• Colossal magnetocapacitive effect in differently synthesized and doped CdCr2S4
• Order Parameters and Phase Diagram of Multiferroic RMn${}_2$O${}_5$
• Order Parameters and Phase Diagrams of Multiferroics
• Electromagnon excitations in modulated multiferroics
• Theory of magnetic field-induced metaelectric critical end point in BiMn${}_2$O${}_5$