Symmetry breaking, slow relaxation dynamics, and topological defects at the field-induced helix reorientation in MnSi

Abstract

We report a study of the reorientation of the helimagnetic order in the archetypal cubic chiral magnet MnSi as a function of magnetic field direction. The reorientation process as inferred from small-angle neutron scattering, the magnetization, and the ac susceptibility is in excellent agreement with an effective mean-field theory taking into account the precise symmetries of the crystallographic space group. Depending on the field and temperature history and the direction of the field with respect to the crystalline axes, the helix reorientation may exhibit a crossover, a first-order, or a second-order transition. The magnetization and ac susceptibility provide evidence that the reorientation of helimagnetic domains is associated with large relaxation times exceeding seconds. At the second-order transitions residual Ising symmetries are spontaneously broken at continuous elastic instabilities of the helimagnetic order. In addition, on the time scales explored in our experiments these transitions are hysteretic as a function of field suggesting, within the same theoretical framework, the formation of an abundance of plastic deformations of the helical spin order. These deformations comprise topologically non-trivial disclinations, promising novel routes to spintronics applications alongside skyrmions discovered recently in the same class of materials.

arXiv comment14 pages, 8 figures + Supplement (8 pages, 9 figures)

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Cited by in corpus (46)

• Collective spin excitations of helices and magnetic skyrmions: review and perspectives of magnonics in non-centrosymmetric magnets
• Emergent topological spin structures in a centrosymmetric cubic perovskite
• Chiral Bobbers and Skyrmions in Epitaxial FeGe/Si(111) Films
• Topological domain walls in helimagnets
• Symmetry-enforced topological nodal planes at the Fermi surface of a chiral magnet
• Thermodynamic evidence of a second skyrmion lattice phase and tilted conical phase in Cu${}_2$0SeO${}_3$
• Microwave spectroscopy of the low-temperature skyrmion state in Cu2OSeO3
• Atomic scale visualization of topological spin textures in the chiral magnet MnGe
• Kinklike structures in models of the Dirac-Born-Infeld type
• Cycloidally modulated magnetic order stabilized by thermal fluctuations in the Néel-type skyrmion host GaV${}_4$S${}_8$
• Screw dislocations in cubic chiral magnets
• Weak crystallization of fluctuating skyrmion textures in MnSi
• Magnetization and ac susceptibility study of the cubic chiral magnet Mn${}_{1-x}$Fe${}_x$Si
• Combing the helical phase of chiral magnets with electric currents
• Magnetic field dependence of the nonlinear magnetic response and tricritical point in the monoaxial chiral helimagnet Cr${}_{1/3}$NbS${}_2$
• Response of the skyrmion lattice in MnSi to cubic magnetocrystalline anisotropies
• Evolution of magneto-crystalline anisotropies in Mn${}_{1-x}$Fe${}_x$Si and Mn${}_{1-x}$Co${}_x$Si as inferred from small-angle neutron scattering and bulk properties
• Ferromagnetic resonance with magnetic phase selectivity by means of resonant elastic x-ray scattering on a chiral magnet
• Disordered skyrmion phase stabilized by magnetic frustration in a chiral magnet
• Field and anisotropy driven transformations of spin spirals in cubic skyrmion hosts
• Signatures of a liquid-crystal transition in spin-wave excitations of skyrmions
• Magnetic field control of cycloidal domains and electric polarization in multiferroic BiFeO${}_3$
• Helitronics for classical and unconventional computing
• Relaxation dynamics of modulated magnetic phases in skyrmion host GaV4S8: an ac magnetic susceptibility study
• Helical and skyrmion lattice phases in three-dimensional chiral magnets: Effect of anisotropic interactions
• Precipitating Ordered Skyrmion Lattices from Helical Spaghetti
• Field-induced reorientation of helimagnetic order in Cu${}_2$OSeO${}_3$ probed by magnetic force microscopy
• Increasing the skyrmion stability in Cu${}_2$OSeO${}_3$ by chemical substitution
• Trapping Majorana Zero Modes in Vortices of Magnetic Texture Crystals Coupled to Nodal Superconductors
• Tunable Cooperativity in Coupled Spin--Cavity Systems
• Critical Sample Aspect Ratio and Magnetic Field Dependence for Antiskyrmion Formation in Mn1.4PtSn Single-Crystals
• Unpinning the skyrmion lattice in MnSi:Effect of substitutional disorder
• Observation by SANS and PNR of pure Néel-type domain wall profiles and skyrmion suppression below room temperature in magnetic [Pt/CoFeB/Ru]${}_{10}$ multilayers
• Gyrotropic elastic response of skyrmion crystals to current-induced tensions
• Robust cycloid crossover driven by anisotropy in the skyrmion host GaV${}_4$S${}_8$
• Magnetic properties of the noncentrosymmetric tetragonal antiferromagnet EuPtSi${}_3$
• Non-equilibrium structural phase transitions of the vortex lattice in MgB2
• Resonant elastic X-ray scattering of antiferromagnetic superstructures in EuPtSi${}_3$
• Compositional Studies of Metals with Complex Order by means of the Optical Floating-Zone Technique
• Effect of chemical substitution on the skyrmion phase in Cu${}_2$OSeO${}_3$
• Scalar field models driven by Dirac-Born-Infeld dynamics and their relatives
• Structure and magnetism of MnGe thin films grown with a nonmagnetic CrSi template
• Evolution of magnetic bubble domains in the uniaxial ferromagnet CeRu${}_2$Ga${}_2$B inferred from the Hall effect and ac magnetic susceptibility
• Kinklike structures in an arcsin real scalar dynamics
• A $C^{\ast }$-algebraic view on the interaction of real- and reciprocal space topology in skyrmion crystals
• Archimedean Screw in Driven Chiral Magnets