A theoretical analysis of inertia-like switching in magnets: applications to a synthetic antiferromagnet

TL;DR

This paper provides a theoretical analysis of inertia-like switching in synthetic antiferromagnets, revealing rapid magnetization dynamics driven by energy redistribution, with implications for magnetic switching technologies.

Contribution

It introduces a theoretical framework explaining inertia-like magnetization switching without relying on the inertia concept, supported by first-principles and atomistic simulations.

Findings

Switching occurs within tens of picoseconds.

Inertia-like behavior results from energy redistribution among magnetic terms.

Dynamics also observed in ferromagnetic materials with energy pumped into magnetic anisotropy.

Abstract

The magnetization dynamics of a synthetic antiferromagnet subject to a short magnetic field pulse, has been studied by using a combination of first-principles and atomistic spin dynamics simulations. We observe switching phenomena on the time scale of tens of picoseconds, and inertia-like behavior in the magnetization dynamics. We explain the latter in terms of a dynamic redistribution of magnetic energy from the applied field pulse to other possible energy terms, such as the exchange interaction and the magnetic anisotropy, without invoking concepts such as inertia of an antiferromagnetic vector. We also demonstrate that such dynamics can also be observed in a ferromagnetic material where the incident field pulse pumps energy to the magnetic anisotropy.