Understanding of the interaction of antiferromagnetic solitons including domain walls and skyrmions with boundaries of chiral antiferromagnetic slabs is important for the design of prospective ...antiferromagnetic spintronic devices. Here, we derive the transition from spin lattice to micromagnetic nonlinear σ model with the corresponding boundary conditions for a chiral cubic G-type antiferromagnet and analyze the impact of the slab boundaries and antisymmetric exchange (Dzyaloshinskii-Moriya interaction) on the vector order parameter. We apply this model to evaluate modifications of antiferromagnetic domain walls and skyrmions upon interaction with boundaries for different strengths of the antisymmetric exchange. Due to the presence of the antisymmetric exchange, both types of antiferromagnetic solitons become broader when approaching the boundary and transform to a mixed Bloch-Néel structure. Both textures feel the boundary at the distance of about five magnetic lengths. In this respect, our model provides design rules for antiferromagnetic racetracks, which can support bulklike properties of solitons.
Under the action of an alternating perpendicular magnetic field, the polarity of the vortex state nanodisk can be efficiently switched. We predict the regular and chaotic dynamics of the vortex ...polarity and propose a simple analytical description in terms of a reduced vortex core model. Conditions for the controllable polarity switching are analyzed.
The vortex core shape in the three dimensional Heisenberg magnet is essentially influenced by a surface anisotropy. We predict that depending of the surface anisotropy type there appears barrel- or ...pillow-shaped deformation of the vortex core along the magnet thickness. Our theoretical study is well confirmed by spin–lattice simulations.
•The shape of magnetic vortex core is essentially influenced by SA (surface anisotropy).•We predict barrel- or pillow-shaped deformation of the vortex depending on SA.•The variational approach fully describes the vortex core deformation.•We performed spin–lattice simulations to detect SA influence on the vortex core.
Antiferromagnets are normally thought of as materials with compensated magnetic sublattices. This adds to their technological advantages but complicates readout of the antiferromagnetic state. We ...demonstrate theoretically the existence of a Dzyaloshinskii-Moriya interaction (DMI), which is determined by the magnetic symmetry classes of Cr_{2}O_{3} surfaces with an in-plane magnetic easy axis. The DMI explains a previously predicted out-of-plane magnetization at the nominally compensated surfaces of chromia, leading to a surface-localized canted ferrimagnetism. This is in agreement with magnetotransport measurements and with density functional theory predictions that further allow us to quantify the strength of DMI. The temperature dependence of the transversal resistance for these planes shows distinct behavior in comparison with that of the Cr_{2}O_{3} c plane, which we attribute to the influence of DMI. Our Letter provides a framework to analyze surface-driven phenomena in antiferromagnets, and motivates the use of nominally compensated chromia surfaces for antiferromagnetic spintronics and magnonics.Antiferromagnets are normally thought of as materials with compensated magnetic sublattices. This adds to their technological advantages but complicates readout of the antiferromagnetic state. We demonstrate theoretically the existence of a Dzyaloshinskii-Moriya interaction (DMI), which is determined by the magnetic symmetry classes of Cr_{2}O_{3} surfaces with an in-plane magnetic easy axis. The DMI explains a previously predicted out-of-plane magnetization at the nominally compensated surfaces of chromia, leading to a surface-localized canted ferrimagnetism. This is in agreement with magnetotransport measurements and with density functional theory predictions that further allow us to quantify the strength of DMI. The temperature dependence of the transversal resistance for these planes shows distinct behavior in comparison with that of the Cr_{2}O_{3} c plane, which we attribute to the influence of DMI. Our Letter provides a framework to analyze surface-driven phenomena in antiferromagnets, and motivates the use of nominally compensated chromia surfaces for antiferromagnetic spintronics and magnonics.
Dynamics of topological magnetic textures are typically induced externally by, e.g., magnetic fields or spin/charge currents. Here, we demonstrate the effect of the internal-to-the-system ...geometry-induced motion of a domain wall in a curved nanostripe. Being driven by a gradient of the curvature of a stripe with biaxial anisotropy, transversal domain walls acquire remarkably high velocities of up to 100m/s and do not exhibit any Walker-type speed limit. We pinpoint that the inhomogeneous distribution of the curvature-induced Dzyaloshinskii-Moriya interaction is a driving force for the motion of a domain wall. Although we showcase our approach on the specific Euler spiral geometry, the approach is general and can be applied to a wide class of geometries.
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