Magnon spectrum of the helimagnetic insulator Cu2OSeO3

• DOI: 10.1038/ncomms10725
• Publication Date: 2016-02-25T10:28:08Z
• Authors: P. Y. Portnichenko; J. Romhányi; Y. A. Onykiienko; A. Henschel; M. Schmidt; A. S. Cameron; M. A. Surmach; J. A. Lim; J. T. Park; A. Schneidewind; D. L. Abernathy; H. Rosner; Jeroen van den Brink; D. S. Inosov
• Keywords: Magnon; Skyrmion; Spin wave

Abstract Complex low-temperature-ordered states in chiral magnets are typically governed by a competition between multiple magnetic interactions. The chiral-lattice multiferroic Cu 2 OSeO 3 became the first insulating helimagnetic material which 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 full three-dimensional spin-excitation spectrum over broad range energies. Distinct types high- and low-energy dispersive magnon modes separated an extensive energy gap observed excellent agreement with previously suggested microscopic theory based on model entangled 4 tetrahedra. comparison our spectroscopy data spin-dynamical calculations these theoretical proposals enables accurate quantitative verification fundamental interactions that essential for understanding its abundant low-temperature magnetically ordered phases.