MAGNETISATION REVERSAL AND DOMAIN STRUCTURE IN THIN MAGNETIC FILMS: THEORY AND COMPUTER SIMULATION

TL;DR

This paper presents a theoretical and computational study of magnetic reversal and domain structures in nanoscale thin magnetic films with high perpendicular anisotropy, incorporating disorder, temperature effects, and dynamics.

Contribution

It introduces a comprehensive model combining exchange, dipolar forces, anisotropy, and disorder, validated by Monte Carlo simulations matching experimental observations.

Findings

Hysteresis loops consistent with experiments

Domain configurations depend on film thickness

Reversal dynamics captured accurately by simulations

Abstract

A model is introduced for the theoretical description of nanoscale magnetic films with high perpendicular anisotropy. In the model the magnetic film is described in terms of single domain magnetic grains, interacting via exchange as well as via dipolar forces. Additionally, the model contains anisotropy energy and a coupling to an external magnetic field. Disorder is taken into account in order to describe realistic domain and domain wall structures. Within this framework the dependence of the energy on the film thickness can be discussed. The influence of a finite temperature as well as the dynamics can be modeled by a Monte Carlo simulation. The results on the hysteresis loops, the domain configurations, and the dynamics during the reversal process are in good agreement with experimental findings.