Model for twin electromagnons and magnetically induced oscillatory polarization in multiferroic RMnO${}_3$

Abstract

We propose a model for the pair of electromagnon excitations observed in the class of multiferroic materials {\it R}MnO${}_3$ ({\it R} is a rare-earth ion). The model is based on a harmonic cycloid ground state interacting with a zone-edge magnon and its twin excitation separated in momentum space by two times the cycloid wave vector. The pair of electromagnons is activated by cross coupling between magnetostriction and spin-orbit interactions. Remarkably, the spectral weight of the twin electromagnon is directly related to the presence of a magnetically induced oscillatory polarization in the ground state. This leads to the surprising prediction that TbMnO${}_3$ has an oscillatory polarization with amplitude 50 times larger than its uniform polarization.

4 pages, 3 figures

References in corpus (14)

• Spin current and magneto-electric effect in non-collinear magnets
• Ferroelectricity in spiral magnets
• Role of the Dzyaloshinskii-Moriya interaction in multiferroic perovskites
• Magnetic inversion symmetry breaking and ferroelectricity in TbMnO3
• Possible evidence for electromagnons in multiferroic manganites
• Dynamical magneto-electric coupling in helical magnets
• Observation of electromagnon excitations in the BiFe0${}_3$ spiral magnet
• Electromagnons in multiferroic YMn2O5 and TbMn2O5
• First-principles study of improper ferroelectricity in TbMnO3
• Origin of electromagnon excitations in \textit{R}MnO${}_3$
• Electrically driven spin excitation in a ferroelectric magnet DyMnO_3
• Optical coupling to spin waves in the cycloidal multiferroic BiFeO3
• Magnetic and magnetoelectric excitations in TbMnO${}_3$
• Giant magnetoelectric effect induced by intrinsic surface stress in ferroic nanorods

Cited by in corpus (22)

• Theory of electromagnon in the multiferroic Mn perovskites: Vital role of higher harmonic components of the spiral spin order
• Nonreciprocal Directional Dichroism and Toroidalmagnons in Helical Magnets
• Evidence of electro-active excitation of the spin cycloid in TbMnO3
• Electric field control of terahertz polarization in a multiferroic manganite with electromagnons
• Magneto-electric excitations in multiferroic TbMnO3 by Raman scattering
• Spin and lattice excitations of a BiFeO3 thin film and ceramics
• Electromagnon in the Z-type hexaferrite $({\mathrm{Ba}}_x{\mathrm{Sr}}_{1-x}{)}_3\mathrm{C}{\mathrm{o}}_2\mathrm{F}{\mathrm{e}}_{24}{\mathrm{O}}_{41}$
• Magnetic field induced dehybridization of the electromagnons in multiferroic TbMnO3
• Electromagnon and phonon excitations in multiferroic TbMnO3
• Magnons and Magnetodielectric Effects in CoCr${}_2$O${}_4$: Raman Scattering Studies
• Possible coupling between magnons and phonons in multiferroic CaMn7O12
• Soft-mode behavior of electromagnons in multiferroic manganite
• Magnetic order and electromagnon excitations in DyMnO3 studied by neutron scattering experiments
• Sinusoidal electromagnon in RMnO3: Indication of anomalous magnetoelectric coupling
• Electromagnons in the multiferroic state of perovskite manganites with symmetric-exchange striction
• High-Frequency Electromagnon in GdMnO3
• Terahertz magnetoelectric response via electromagnons in magnetic oxides
• Electromagnon in ferrimagnetic eps-Fe2O3 nanograin ceramics
• Spin-wave dispersion and magnon chirality in multiferroic TbMnO3
• Molecular-spin dynamics study of electromagnons in multiferroic RMn${}_2$O${}_5$
• Modifying the magnetoelectric coupling in TbMnO${}_3$ by low-level Fe${}^{3+}$ substitution
• Elastic and magnetoelastic properties of TbMnO3 single crystal by nanosecond time resolved acoustics and first-principles calculations