Criterion of multi-switching stability for magnetic nanoparticles

TL;DR

This paper develops a criterion for multi-switching stability in magnetic nanoparticles, enabling comparison of switching schemes and analyzing effects of temperature, particle shape, and dipolar interactions through micromagnetic simulations.

Contribution

It introduces a new stability criterion for magnetic nanoparticle switching, applicable at room temperature and considering dipolar interactions, with validation via micromagnetic simulations.

Findings

Stable switching achievable at room temperature with CMOS-like pulses.

Dipolar interactions influence switching stability and are accounted for.

Switching rates in GHz regime are feasible with the proposed criterion.

Abstract

We present a procedure to study the switching and the stability of an array of magnetic nanoparticles in the dynamical regime. The procedure leads to the criterion of multi-switching stability to be satisfied in order to have stable switching. The criterion is used to compare various magnetic-field-induced switching schemes, either present in the literature or suggested in the present work. In particular, we perform micromagnetic simulations to study the magnetization trajectories and the stability of the magnetization after switching for nanoparticles of elliptical shape. We evaluate the stability of the switching as a function of the thickness of the particles and the rise and fall times of the magnetic pulses, both at zero and room temperature. Furthermore, we investigate the role of the dipolar interaction and its influence on the various switching schemes. We find that the criterion of multi-switching stability can be satisfied at room temperature and in the presence of dipolar interactions for pulses shaped according to CMOS specifications, for switching rates in the GHz regime.