Related papers: Including nanoparticle shape into macrospin models
We extend a renormalization group-based course-graining method for micromagnetic simulations to include properly scaled magnetostatic interactions. We apply the method in simulations of dynamic hysteresis loops at clinically relevant sweep…
Highly sophisticated synthesis methods and experimental techniques allow for precise measurements of magnetic properties of nanoparticles that can be reliably reproduced using theoretical models. Here, we investigate the magnetic properties…
Iron oxide magnetic nanoparticles (NPs) are stimuli-responsive materials at the forefront of nanomedicine. Their realistic finite temperature simulations are a formidable challenge for first-principles methods. Here, we use density…
The equilibrium states of single-domain magnetite nanoparticles (NPs) result from a subtle interplay between size, geometry, and magnetocrystalline anisotropy. In this work, we present a micromagnetic study of shape-controlled magnetite NPs…
We review some recent results beyond the now established theory of magnetization switching of a nanoparticle within the single-spin approximation. The first extension is that of the Stoner-Wohlfarth model for magnetization static switching…
We demonstrate how micromagnetic simulations can be employed in order to characterize and analyze the magnetic microstructure of nanocomposites. For the example of nanocrystalline Nd$-$Fe$-$B, which is a potential material for future…
Magnetodynamical properties of nanomagnets are affected by the demagnetizing fields created by the same nanoelements. In addition, magnetocrystalline anisotropy produces an effective field that also contributes to the spin dynamics. In this…
Atomistic modelling of magnetic materials provides unprecedented detail about the underlying physical processes that govern their macroscopic properties, and allows the simulation of complex effects such as surface anisotropy, ultrafast…
We present an analytical framework that predicts and controls nanoparticle size through external magnetic fields, uniting first-principles thermodynamics with a sphere packing approach. Calibrated to diamagnetic silver nanoparticles (20 nm…
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…
In the search for rare-earth free permanent magnets, various ideas related to shape anisotropy are being pursued. In this work we assess the limits of shape contributions to the reversal stability using micromagnetic simulations. In a first…
We develop and validate a computational approach to nanomagnets. It is built on the spin wave approximation to a Heisenberg ferromagnet whose parameters can be calculated from a first principles theory (e.g. density functional theory). The…
Micromagnetic simulation results on dynamic hysteresis loops of clusters of iron oxide nanoparticles (NPs) with internal structure composed of nanorods are compared with the widely used macrospin approximation. Such calculations allowing…
Motivated by the importance of magnetization dynamics in nanomagnets for the development and optimization of magnetic devices and sensors, we measured and modeled spin wave spectra in patterned elliptical nanomagnets. Ferromagnetic…
We report on spin atomistic calculations used to model static and dynamic magnetic properties of inhomogeneous ultrathin iron films. Active magnetic layers in next-generation spintronic devices are becoming so thin that they exhibit some…
We examine the reduction of silver nanoparticle (AgNP) size under an external magnetic field within a classical nucleation theory framework combined with a sphere-packing description of atomic assembly. The model incorporates magnetic…
We developed a micromagnetic method for modeling magnetic systems with periodic boundary conditions along an arbitrary number of dimensions. The main feature is an adaptation of the Ewald summation technique for evaluation of long-range…
The magnetization curves of densely packed single domain magnetic nanoparticles (MNP) are investigated by Monte Carlo simulations in the framework of an effective one spin model. The particles whose size polydispersity is taken into account…
Some of the synthesis methods and physical properties of iron-oxide based magnetic nanoparticles such as Fe3-xO4 and CoxFe3-xO4 are reviewed because of their interest in health, environmental applications, and ultra-high-density magnetic…
We study the finite-size and surface effects on the thermal and spatial behaviors of the magnetisation of a small magnetic particle. We consider two systems: 1) A box-shaped isotropic particle of simple cubic structure with either periodic…