Noise-induced effects in magnetization reversal and chirality control of circular array of single-domained nanomagnets

TL;DR

This study uses computer simulations to analyze how noise affects the speed and reliability of magnetization reversal in a pentagonal array of nanomagnets, revealing optimal conditions for minimizing switching time and variability.

Contribution

It demonstrates the influence of noise and geometric parameters on magnetization reversal, identifying optimal pulse and angle conditions to enhance switching performance.

Findings

Optimal pulse duration minimizes switching time and variability.

Reversal efficiency depends on the angle between magnetic field and array edge.

Significant reduction in mean switching time from 60 ns to 2-3 ns achieved.

Abstract

The effect of noise on the process of high-speed remagnetization of vortex state of a pentagonal array of five circular magnetic nanoparticles is studied by means of computer simulation of Landau-Lifshits model. The mean switching time and its standard deviation of the reversal between the counterclockwise and clockwise vorticities have been computed. It has been demonstrated that with the reversal by the pulse with sinusoidal shape, the optimal pulse duration exists, which minimizes both the mean switching time (MST) and the standard deviation (SD). Besides, both MST and SD significantly depend on the angle between the reversal magnetic field and pentagon edge, and the optimal angle roughly equals 10 degrees. Also, it is demonstrated that the optimization of the angle, duration and the amplitude of the driving field leads to significant decrease of both MST and SD. In particular, for the considered parameters, the MST can be decreased from 60 ns to 2-3 ns. Such a chain of magnetic nanoparticles can effectively be used as an element of magnetoresistive memory, and at the temperature 300K the stable operation of the element is observed up to rather small size of nanoparticles with the raduis of 20 nm.