Autoresonant control of the magnetization switching in single-domain nanoparticles

TL;DR

This paper demonstrates that autoresonant control using a slowly varying microwave frequency can efficiently switch magnetization in nanoparticles, reducing energy input and enabling rapid, simultaneous switching of multiple magnetic moments.

Contribution

It introduces a microwave autoresonance technique for magnetization switching that reduces energy requirements and does not need precise parameter tuning.

Findings

Reduced applied field by over 30% using autoresonance.

Efficient simultaneous switching of multiple magnetic moments.

Dipolar interactions mitigate temperature effects in nanoparticle chains.

Abstract

The ability to control the magnetization switching in nanoscale devices is a crucial step for the development of fast and reliable techniques to store and process information. Here we show that the switching dynamics can be controlled efficiently using a microwave field with slowly varying frequency (autoresonance). This technique allowed us to reduce the applied field by more than $30%$ compared to competing approaches, with no need to fine-tune the field parameters. For a linear chain of nanoparticles the effect is even more dramatic, as the dipolar interactions tend to cancel out the effect of the temperature. Simultaneous switching of all the magnetic moments can thus be efficiently triggered on a nanosecond timescale.