A local bend of a nanowire is a source of pinning potential for a transversal head-to-head (tail-to-tail) domain wall. Eigenfrequency of the domain wall free oscillations at the pinning potential and the effective friction are determined as functions of the curvature and domain wall width. The pinning potential originates from…
A magnetic helix wire is one of the simplest magnetic systems which manifests properties of both curvature and torsion. Possible equilibrium magnetization states in the helix wire with different anisotropy directions are studied theoretically. There exist two equilibrium states in the helix wire with easy-tangential anisotropy: a quasitangential magnetization distribution…
A spin-polarized electrical current leads to a variety of periodical magnetic structures in nanostripes. In the presence of the Ørsted field, which always assists an electrical current, the basic types of magnetic structures, i.e., a vortex-antivortex crystal and cross-tie domain walls, survive. The Ørsted field prevents saturation of the nanostripe…
Chirality symmetry breaking is a common phenomenon in the Nature. The most intriguing examples come from life sciences (chirality symmetry breaking of biological macromolecules, such as DNA) and from particle physics (e.g. neutrino helicity symmetry breaking). In magnetism, chirality is a characteristic of a number of topologically nontrivial structures, such…
Vortex core reversal in magnetic particle is essentially influenced by a surface anisotropy. Under the action of a perpendicular static magnetic field the vortex core undergoes a shape deformation of pillow- or barrel-shaped type, depending on the type of the surface anisotropy. This deformation plays a key point in the…
Nowadays there is a growing interest in studying of topological structures in curved magnetic objects such as magnetic nanowires and nanoshells. We develop an approach to treat magnetic energy of a ferromagnet for arbitrary curved wires and shells on the assumption that the anisotropy contribution greatly exceeds the dipolar and…
The submbicron-scaled magnetism of solid state is a rapidly developing research area with a promising applied potential. Nanomagnets are often considered as elements of fast nonvolatile memory devices of high density. Up to now the theoretical study in this direction was restricted mostly by planar structures. In the current research…
Object Oriented Micromagnetic Framework (OOMMF) is free, portable, extensible public domain micromagnetic program and associated tools, which was developed at the National Institute of Standards and Technology (NIST). OOMMF is very powerful and useful tool which can be thinly configured for different micromagnetic studies, but at the same time, it…
We investigated the influence of a spin-polarized current on long ferromagnetic nanostripes. The magnetization behavior is analyzed for all range of the applied currents, up to the saturation. It is shown that the saturation current is a nonmonotonic function of the stripe width. For a stripe width increasing it approaches…
We predict the regular and chaotic dynamics of the vortex polarity under the action of perpendicular ac magnetic field and propose a simple analytical description in terms of a reduced vortex core model. Phys. Rev. B, 88, 014432 (2013), 10.1103/PhysRevB.88.014432, PDF.