Quantitative simulation of temperature dependent magnetization dynamics and equilibrium properties of elemental ferromagnets

TL;DR

This paper introduces a rescaling method for atomistic spin models that accurately predicts temperature-dependent magnetization and ultrafast dynamics of elemental ferromagnets, aligning simulations with experimental results.

Contribution

A single-parameter rescaling approach is proposed to correct temperature dependence in atomistic spin simulations, improving their quantitative accuracy.

Findings

Rescaling thermal fluctuations aligns simulation with experimental magnetization data.

The method accurately predicts ultrafast magnetization dynamics of Ni under laser pulses.

Enables precise simulations of magnetic properties across all temperatures.

Abstract

Atomistic spin model simulations are immensely useful in determining temperature dependent magnetic prop- erties, but are known to give the incorrect dependence of the magnetization on temperature compared to exper- iment owing to their classical origin. We find a single parameter rescaling of thermal fluctuations which gives quantitative agreement of the temperature dependent magnetization between atomistic simulations and experi- ment for the elemental ferromagnets Ni, Fe, Co and Gd. Simulating the sub-picosecond magnetization dynam- ics of Ni under the action of a laser pulse we also find quantitative agreement with experiment in the ultrafast regime. This enables the quantitative determination of temperature dependent magnetic properties allowing for accurate simulations of magnetic materials at all temperatures.