title: Origin of electromagnon excitations in multiferroic RMnO3.
abstract: Electromagnon excitations in multiferroic orthorhombic RMnO3 are shown to result from the Heisenberg coupling between spins despite the fact that the static polarization arises from the much weaker Dzyaloshinskii-Moriya exchange interaction. We present a model incorporating the structural characteristics of this family of manganites that is confirmed by far infrared transmission data as a function of temperature and magnetic field and inelastic neutron scattering results. A deep connection is found between the magnetoelectric dynamics of the spiral phase and the static magnetoelectric coupling in the collinear E phase of this family of manganites.
authors.affiliation: Department of Physics, University of Maryland, College Park, Maryland 20742, USA. rvaldes@physics.umd.edu
authors.forename: R
authors.initials: R
authors.lastname: Valdés Aguilar
authors.forename: M
authors.initials: M
authors.lastname: Mostovoy
authors.forename: A B
authors.initials: AB
authors.lastname: Sushkov
authors.forename: C L
authors.initials: CL
authors.lastname: Zhang
authors.forename: Y J
authors.initials: YJ
authors.lastname: Choi
authors.forename: S-W
authors.initials: SW
authors.lastname: Cheong
authors.forename: H D
authors.initials: HD
authors.lastname: Drew