title: Ultrafast optical excitation of magnetic skyrmions.
abstract: Magnetic skyrmions in an insulating chiral magnet Cu2OSeO3 were studied by all-optical spin wave spectroscopy. The spins in the conical and skyrmion phases were excited by the impulsive magnetic field from the inverse-Faraday effect, and resultant spin dynamics were detected by using time-resolved magneto-optics. Clear dispersions of the helimagnon were observed, which is accompanied by a distinct transition into the skyrmion phase, by sweeping temperature and magnetic field. In addition to the collective excitations of skyrmions, i.e., rotation and breathing modes, several spin precession modes were identified, which would be specific to optical excitation. The ultrafast, nonthermal, and local excitation of the spin systems by photons would lead to the efficient manipulation of nano-magnetic structures.
authors.affiliation: RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Ogawa
authors.affiliation: 1] RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198, Japan [2] PRESTO, Japan Science and Technology Agency, Tokyo 102-0075, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Seki
authors.affiliation: 1] RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198, Japan [2] Department of Applied Physics and Quantum Phase Electronics Center (QPEC), University of Tokyo, Tokyo 113-8656, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Tokura