Chiral magnetic skyrmions arise due to the Dzyaloshinskii-Moriya interaction (DMI) as a result of the spin-orbit interaction in magnets lacking bulk or structure inversion asymmetry. I start my talk with a micromagnetic formulation of the energy functional and discuss briefly some general fundamental aspects. Using then a three-pronged scale-bridging approach combining DFT calculations with a...
Antiferromagnetic skyrmion crystals are spatially periodic noncollinear magnetic phases predicted to exist in antiferromagnets with Dzyaloshinskii-Moriya interactions. We show for the first time that their bulk magnon band structure, characterized by nonzero Chern numbers, is topologically nontrivial and that they support topologically-protected chiral magnonic edge states. Of particular...
The nanometer-scale vortex-like spin textures, such as vortex-anrivortex pairs in ferromagnetic (FM) domain walls [1], votices in superconductors [2], skyrmion (lattice) [3] and antiskyrmions [4] in magnets with inversion symmetry, have recently attracted enormous attention owing to their topological manner[5]. To confirm such minute complex spin textures and their dynamics with external...
In a β-Mn-type chiral magnet Co9Zn9Mn2, we demonstrate the magnetic field-driven collapse of a room temperature metastable skyrmion lattice (SkL) to pass through a regime of partial topological charge inversion. Using Lorentz transmission electron microscopy, we observe the magnetization distribution directly as magnetic fields are applied antiparallel to the original skyrmion core...
Skyrmions are topologically protected spin textures that appear in certain chiral magnetic materials. One bulk chiral material in which skyrmions are observed is the multiferroic insulator Cu2OSeO3. In this talk I will present small angle neutron scattering (SANS) and magnetometry work studying skyrmion metastability in zinc-substituted Cu2OSeO3. This substitution dramatically increases the...
The chiral ferrimagnet Cu2OSeO3 hosts topologically protected spin textures known as magnetic skyrmion lattices and exhibit characteristic magnon band structures. We conducted scanning Brillouin light scattering (BLS) spectroscopy on bulk-shape single crystals of Cu2OSeO3 at low temperature with magnetic field applied along (100). Multiple magnon modes were observed in conical and...
Neutron scattering was used to study frustrated MnSc2S4 spinel with magnetic Mn2+ ions forming the diamond lattice [1]. We present direct experimental evidence for the existence of the spiral spin liquid, which was predicted to occur within the J1-J2 model, when the ratio between the first and second neighbour couplings is |J2/J1|>0.125, unravel three long-range ordered phases supplanting each...
