Complex field reversal dynamics in nanomagnetic systems

TL;DR

This paper investigates the dynamics of magnetic field reversal in nanomagnetic systems using the Glauber mean-field model, revealing analytical solutions in 1D and complex fractal patterns in higher dimensions.

Contribution

It introduces an analytical approach to understanding nanomagnetic reversal dynamics across different dimensions, highlighting the formation of fractal clusters.

Findings

Analytical solutions for 1D and tree structures at zero temperature.

Fractal reversal clusters in 2D and 3D depend on field strength.

Harmonic power spectra from spin flip cascades.

Abstract

Nanomagnetic materials, built from thin, patterned films of ferromagnetic materials, began as analogues to frustrated magnetism. Their low energy of operation and emergent properties make them strong candidates for physics based devices. A recent model of how nanomagnetic domains flip, the Glauber mean-field model, is used here to understand how systems of nanomagnets evolve when opposed by external field. This reversal can be expressed in an analytical form in the case of one-dimensional chains and trees at zero temperature, where the cascade of spin flips gives rise to harmonic power spectra. The same cascades in two and three dimensions form fractal field reversal clusters whose shape depends on the strength of the field and the tuning of interactions between nanomagnets.