Electromagnons in multiferroic RMn2O5 compounds and their microscopic origin

Abstract

We summarize the existing experimental data on electromagnons in multiferroic RMn2O5 compounds, where R denotes a rare earth ion, Y or Bi, and discuss a realistic microscopic model of these materials based on assumption that the microscopic mechanism of magnetically-induced ferroelectricity and electromagnon absorption relies entirely on the isotropic Heisenberg exchange and magnetostrictive coupling of spins to a polar lattice mode and does not involve relativistic effects. This model explains many magnetic and optical properties of RMn2O5 manganites, such as the spin re-orientation transition, magnetically-induced polarisation, appearance of the electromagnon peak in the non-collinear spin state and the polarisation of light for which this peak is observed. We compare experimental and theoretical results on electromagnons in RMn2O5 and RMnO3 compounds.

20 pages, 9 figures, to be published in J. Phys.: Condens. Matter, special issue on multiferroics

References in corpus (14)

• 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
• Magnetically driven ferroelectric order in Ni${}_3$V${}_2$O${}_8$
• Ferroelectricity in the Magnetic E-Phase of Orthorhombic Perovskites
• Spin-polarization coupling in multiferroic transition-metal oxides
• Dynamical magneto-electric coupling in helical magnets
• Coupling of phonons and electromagnons in GdMnO_3
• Optical coupling to spin waves in the cycloidal multiferroic BiFeO3
• Colossal magnon-phonon coupling in multiferroic Eu${}_{0.75}$Y${}_{0.25}$MnO${}_3$
• Terahertz spectroscopy of electromagnons in Eu_{1-x}Y_xMnO_3
• Electrical control of magnon propagation in multiferroic BiFeO3 films
• Order Parameters and Phase Diagram of Multiferroic RMn${}_2$O${}_5$
• An Effective Model of Magnetoelectricity in Multiferroics $RM{n}_2{O}_5$

Cited by in corpus (4)

• Origin of electromagnon excitations in \textit{R}MnO${}_3$
• Magnetic and magnetoelectric excitations in TbMnO${}_3$
• Spin-driven Phase Transitions in ZnCr${}_2$Se${}_4$ and ZnCr${}_2$S${}_4$ Probed by High Resolution Synchrotron X-ray and Neutron Powder Diffraction
• Theory of magnetic field-induced metaelectric critical end point in BiMn${}_2$O${}_5$