title: Electromagnons in multiferroic YMn2O5 and TbMn2O5.
abstract: Based on temperature dependent far infrared transmission spectra of YMn2O5 and TbMn2O5 single crystals, we report the observation of electric dipole-active magnetic excitations, or electromagnons, in these multiferroics. Electromagnons are found to be directly responsible for the steplike anomaly of the static dielectric constant at the commensurate--incommensurate magnetic transition and are the origin of the colossal magneto-dielectric effect reported in these multiferroics.
authors.affiliation: Materials Research Science and Engineering Center, University of Maryland, College Park, Maryland 20742, USA.
authors.forename: A B
authors.initials: AB
authors.lastname: Sushkov
authors.forename: R Valdés
authors.initials: RV
authors.lastname: Aguilar
authors.forename: S
authors.initials: S
authors.lastname: Park
authors.forename: S-W
authors.initials: SW
authors.lastname: Cheong
authors.forename: H D
authors.initials: HD
authors.lastname: Drew