CC BY 4.0 UnportedPortnichenko, P.Y.Romhányi, J.Onykiienko, Y.A.Henschel, A.Schmidt, M.Cameron, A.S.Surmach, M.A.Lim, J.A.Park, J.T.Schneidewind, A.Abernathy, D.L.Rosner, H.van den Brink, JeroenInosov, D.S.2018-06-072019-06-282016https://doi.org/10.34657/4986https://oa.tib.eu/renate/handle/123456789/1496Complex low-temperature-ordered states in chiral magnets are typically governed by a competition between multiple magnetic interactions. The chiral-lattice multiferroic Cu2OSeO3 became the first insulating helimagnetic material in which a long-range order of topologically stable spin vortices known as skyrmions was established. Here we employ state-of-the-art inelastic neutron scattering to comprehend the full three-dimensional spin-excitation spectrum of Cu2OSeO3 over a broad range of energies. Distinct types of high- and low-energy dispersive magnon modes separated by an extensive energy gap are observed in excellent agreement with the previously suggested microscopic theory based on a model of entangled Cu4 tetrahedra. The comparison of our neutron spectroscopy data with model spin-dynamical calculations based on these theoretical proposals enables an accurate quantitative verification of the fundamental magnetic interactions in Cu2OSeO3 that are essential for understanding its abundant low-temperature magnetically ordered phases.application/pdfenghttps://creativecommons.org/licenses/by/4.0/620Magnetic properties and materialsSpintronicsArticle