相关论文: Magnetization states and switching in narrow-gappe…

Ferromagnetic rings exhibit many novel physical phenomena with promise for potential applications. Here, we focus on switching processes which are fundamental properties of magnetic systems and are especially crucial for data storage…

Flexible ferromagnetic rings are spin-chain magnets, in which the magnetic and mechanical subsystems are coupled. The coupling is achieved through the tangentially oriented anisotropy axis. The possibility to operate the mechanics of the…

The switching process of the vortex core in a Permalloy nanodisk affected by a rotating magnetic field is studied theoretically. A detailed description of magnetization dynamics is obtained by micromagnetic simulations.

We image the remnant magnetization configurations of CoFeB and permalloy nanotubes (NTs) using x-ray magnetic circular dichroism photo-emission electron microscopy. The images provide direct evidence for flux-closure configurations,…

We investigate magnetization reversal processes of magnetic nanorings. Using a recently developed efficient cartesian coordinates fast multipole method, magnetization switching phase diagrams are constructed for such structures. We find…

We study the dynamics of flat circular permalloy nanomagnets for 1.) magnetic vortex and 2.) single-domain configurations, using micromagnetic simulation. Dynamical studies for isolated vortex structures show that both the vorticity and the…

The ground state of the ring-shape magnetic nanoparticle is studied. Depending on the geometrical and magnetic parameters of the nanoring, there exist different magnetisation configurations (magnetic phases): two phases with homogeneous…

Within the framework of the Landau-Lifshitz-Gilbert equation, using permalloy parameters, we study the statics and dynamics of flat circular magnetic nano-structures with an in-plane magnetic vortex configuration, putting particular…

We have studied ferromagnetic Permalloy clusters obtained by electrodeposition on n-type silicon. Magnetization measurements reveal hysteresis loops almost independent on temperature and very similar in shape to those obtained in nanodisks…

We fabricated Co nano-rings incorporated in the vertical pseudo-spin-valve nanopillar structures with deep submicron lateral sizes. It is shown that the current-perpendicular-to-plane giant magnetoresistance can be used to characterize a…

Magnetization reversals through the formation of vortex state and the rotation of onion state are two processes with comparable probabilities for symmetric magnetic nanorings with radius of about 50 nanometers. This magnetic bistability is…

We demonstrate a novel method allowing the study of the magnetic state dynamics of a single nanoparticle by means of electron transport measurements. Elliptical 550 nm x 240 nm permalloy nanoparticles are wired with non-magnetic leads for…

Magnetization ground states are studied in toroidal nanomagnets. The energetics associated to the ferromagnetic, vortex and onion-like configurations are explicitly computed. The analysis reveals that the vortex appears to be the most…

Dynamics of magnetic vortex core switching in nanometer-scale permalloy disk, having a single vortex ground state, was investigated by micromagnetic modeling. When an in-plane magnetic field pulse with an appropriate strength and duration…

We present a theory of magnetization reversal due to thermal fluctuations in thin submicron-scale rings composed of soft magnetic materials. The magnetization in such geometries is more stable against reversal than that in thin needles and…

The relative stability of the vortex, onion and ferromagnetic phases in nanorings is examined as a function of the ring geometry. Total energy calculations are carried out analytically, based on simple models for each configuration. Results…

We investigate fundamental processes that govern dynamics of vortex nucleation in sub-100 nm mesoscopic magnets. We focus on a structure with broken symmetry - Pacman-like nanomagnet shape - in which we study micromagnetic behavior both by…

Nano-magnetic systems of artificially shaped ferromagnetic islands, recently became a popular subject due to their current and potential applications in spintronics, magneto-photonics and superconductivity. When the island size is close to…

The magnetic relaxation of ferromagnetic powders has been studied for many years, largely due to its importance to recording technologies. However, only recently have experiments been performed that resolve the magnetic state of individual…

We present results of micromagnetic simulations of thin ferromagnetic rings undergoing magnetization reversal. This geometry is one of few examples in micromagnetics in which the transition states have been found analytically in a 1D model.…