Magnetization reversal in isolated and interacting single-domain nanoparticles

TL;DR

This paper investigates how thermal fluctuations and dipolar interactions influence magnetization reversal in single-domain nanoparticles, combining computational simulations with experimental validation.

Contribution

It introduces a simulation approach using the Fokker-Planck equation with a mean field approximation to model nanoparticle interactions affecting magnetization reversal.

Findings

Interactions can accelerate or decelerate reversal depending on field orientation

Numerical results align well with experimental data on cobalt-platinum nanoparticles

Dipolar interactions significantly influence reversal dynamics

Abstract

Computational and experimental results on the thermally-induced magnetization reversal in single-domain magnetic nanoparticles are reported. The simulations are based on the direct integration of the Fokker-Planck equation that governs the dynamics of the magnetic moment associated with the nanoparticles. A mean field approximation is used to account for the influence of the dipolar interaction between nanoparticles. It is shown that the interactions can either speed up or slow down the reversal process, depending on the angle between the external magnetic field and the axis of easy magnetization. The numerical results are in good agreement with experimental measurements on cobalt-platinum nanoparticles.