Cu2OSeO3 Turns Trigonal with Structural Transformation and Implications for Skyrmions

Abstract

The formation and characteristics of magnetic skyrmions are strongly governed by the symmetry of the underlying crystal structure. In this study, we report the discovery of a new trigonal polymorph of Cu2OSeO3, observed exclusively in nanoparticles. Electron diffraction and density functional theory calculations confirm its R3m space group, sharing C3v symmetry with Néel-type skyrmion hosts. This polymorph is likely stabilized by surface effects, suggesting that size-induced structural changes may drive a transformation from Bloch-type to Neel-type skyrmions in Cu2OSeO3. This hypothesis is consistent with prior unexplained observations of Neel-type skyrmions at the surfaces of bulk crystals, which may result from surface-specific structural distortions. Overall, these findings provide insights into the interplay between size, structure, and magnetism, opening pathways for controlling skyrmionic properties in nanoscale systems.

References in corpus (22)

• Skyrmion Lattice in a Chiral Magnet
• Spontaneous Skyrmion Ground States in Magnetic Metals
• Crystal Hall effect in Collinear Antiferromagnets
• Skyrmion Lattice in a Doped Semiconductor
• Time-reversal symmetry-breaking charge order in a kagome superconductor
• Electric field-induced Skyrmion distortion and giant lattice rotation in the magnetoelectric insulator Cu2OSeO3
• Néel-type skyrmion lattice in tetragonal polar magnet VOSe${}_2$O${}_5$
• Magnetoelectric coupling in the cubic ferrimagnet Cu2OSeO3
• Observation of two independent skyrmion phases in a chiral magnetic material
• Electric-field control of the skyrmion lattice in Cu2OSeO3
• The quantum origins of skyrmions and half-skyrmions in Cu2OSeO3
• Charge order breaks time-reversal symmetry in CsV${}_3$Sb${}_5$
• New magnetic phase of the chiral skyrmion material Cu2OSeO3
• Ferrimagnetism of the magnetoelectric compound Cu${}_2$OSeO${}_3$ probed by ${}^{77}$Se NMR
• In situ Electric Field Skyrmion Creation in Magnetoelectric Cu${}_2$OSeO${}_3$
• Low spin wave damping in the insulating chiral magnet Cu${}_2$OSeO${}_3$
• Microwave spectroscopy of the low-temperature skyrmion state in Cu2OSeO3
• Room-temperature skyrmion phase in bulk Cu2OSeO3 under high pressures
• Electric field-driven topological phase switching and skyrmion lattice metastability in magnetoelectric Cu${}_2$OSeO${}_3$
• Ferromagnetic resonance with magnetic phase selectivity by means of resonant elastic x-ray scattering on a chiral magnet
• Imaging magnetic spiral phases, skyrmion clusters, and skyrmion displacements at the surface of bulk Cu${}_2$OSeO${}_3$
• Structure analysis of high-pressure phase for skyrmion-hosting multiferroic Cu2OSeO3