Coupled Skyrmion Sublattices inCu2OSeO3

Abstract

We report the observation of a Skyrmion lattice in the chiral multiferroic insulator Cu2OSeO3 using Cu L3-edge resonant soft x-ray diffraction. We observe the unexpected existence of two distinct Skyrmion sublattices that arise from inequivalent Cu sites with chemically identical coordination numbers but different magnetically active orbitals. The Skyrmion sublattices are rotated with respect to each other, implying a long wavelength modulation of the lattice. The modulation vector is controlled with an applied magnetic field, associating this moirélike phase with a continuous phase transition. Our findings will open up a new class of science involving manipulation of quantum topological states.

Resonant elastic x-ray scattering from the skyrmion lattice inCu2OSeO3

“…However, this requires a characterization technique that probes the material on a mesoscopic scale, inbetween the local probing of LTEM and the macroscopic averaging of neutron diffraction. Here, we present resonant soft x-ray scattering on single crystal Cu 2 OSeO 3 , which covers the length scale needed to observe skyrmion domains, revisiting earlier work by Langner et al [16].…”

Nonlinear Ultrafast Spin Scattering in the Skyrmion Phase of Cu2OSeO3

“…1) [22]. This geometry is chosen as a measure of the order parameter dynamics because it is insensitive to the linear and rotational in-plane motions of the hexagonal skyrmion lattice [23]. In both experiments, the sample was excited with 100 fs pump pulses at 1.5 and 3.0 eV, corresponding to excitation below and above the optical gap, which allows us to distinguish between magnetic excitation due to spin-lattice and electron-spin interactions.…”

Coherent Resonant Soft X-ray Scattering Study of Magnetic Textures in FeGe

“…One of the promising applications of coherent soft X-rays is the imaging of the local magnetization of magnetic specimens [7]. In the soft X-ray regime, by exciting electrons from the 2p state to the 3d state of transition-metal atoms, it is possible to study the magnetic ordering in wide-angle diffraction [8][9][10] or small-angle scattering geometry [11][12][13][14][15]. Moreover, a topological winding number of the magnetically ordered system can be directly determined from the polarization-dependent (or dichroic) soft X-ray diffraction pattern alone [16].…”