相关论文: Surface-induced reduction of the switching field i…
We investigate the effect of surface anisotropy in a spherical many-spin magnetic nanoparticle. By computing minor loops, two-dimensional (2D) and 3D energyscape, and by investigating the behavior of the net magnetization, we show that in…
Magnetization reversal in magnetic nanostructures is investigated numerically over time-scales ranging from fast switching processes on a picosecond scale to thermally activated reversal on a microsecond time-scale. A simulation of the…
The interplay between intrinsic and surface/interface-induced magnetic anisotropies strongly in- fluences magnetization processes in nanomagnetic systems. We develop a micromagnetic theory to describe the field-driven reorientation in…
The magnetization reversal of Stoner particles is investigated from the point of view of nonlinear dynamics within the Landau-Lifshitz-Gilbert formulation. The following results are obtained. 1) We clarify that the so-called…
The combination of high sensitive superconducting quantum interference device (SQUID) with high quality nanoparticles allowed to check the simplest classical model describing the magnetisation reversal by uniform rotation which were…
The control of the magnetism of ultra-thin ferromagnetic layers using an electric field rather than a current, if large enough, would lead to many technologically important applications. To date, while it is usually assumed the changes in…
We present a review of recent advances in the study of many-body effects in magnetic nanoparticles. Considering classical spins on a lattice coupled by the exchange interaction in the presence of the bulk and surface anisotropy, we…
We investigate the magnetization dynamics of ferromagnetic nanoparticles in the atomistic approach taking account of surface anisotropy and the spin misalignment it causes. We demonstrate that such inhomogeneous spin configurations induce…
It was experimentally observed that both magnetic anisotropy and spin-orbit interaction strength change when the magnetization of the nanomagnet is reversed. This indicates a variation in spin-orbit interaction strength depending on whether…
Nanoscale superlattices with uniaxial ferromagnetic layers antiferromagnetically coupled through non-magnetic spacers are recently used as components of magnetoresistive and recording devices. In the last years intensive experimental…
The relaxation rate and temperature-dependent switching field curve of a spherical magnetic nanocluster are calculated by taking into account the effect of surface anisotropy via an effective anisotropy model. In particular, it is shown…
The influence of magnetic anisotropy on nanosecond magnetization reversal in coupled FeNi/Cu/Co trilayers was studied using a photoelectron emission microscope combined with x-ray magnetic circular dicroism. In quasi-isotropic samples the…
The influence of surface anisotropy on the magnetization processes of maghemite nanoparticles with ellipsoidal shape is studied by means of Monte Carlo simulations. Radial surface anisotropy is found to favor the formation of hedgehog-like…
Recent experimental and theoretical studies show that the switching behavior of magnetic nanoparticles can be well controlled by external time-dependent magnetic fields. In this work, we inspect theoretically the influence of the…
We present the results of Monte Carlo simulations of the magnetic properties of individual spherical nanoparticles with the aim to explain the role played by surface anisotropy on their low temperature magnetization processes. Phase…
Using micromagnetics we demonstrate that the r.f. field produced by a spin valve can be used to reverse the magnetization in a magnetic nanoparticle. The r.f. field is generated using a current that specifically excites a uniform spin wave…
Using the complex stereographic variable representation for the macrospin, from a study of the nonlinear dynamics underlying the generalized Landau-Lifshitz(LL) equation with Gilbert damping, we show that the spin-transfer torque is…
The reversal condition of magnetization in a nanomagnet under the effect of rotating magnetic field generated by a microwave is theoretically studied based on the Landau-Lifshitz-Gilbert equation. In a rotating frame, the microwave produces…
We study magnetization reversal using various r.f. magnetic pulses. We show numerically that switching is possible with simple sinusoidal pulses; however the optimum approach is to use a frequency-swept (chirped) r.f. magnetic pulse, the…
We study the influence of surface anisotropy on the zero-temperature hysteretic properties of a small single-domain magnetic particle, and give an estimation of the anisotropy constant for which deviations from the Stoner-Wohlfarth model…