Atomistic simulations of magnetoelastic effects on sound velocity

TL;DR

This paper uses atomistic spin-lattice simulations to study how magnetic interactions influence sound wave velocity in ferromagnetic materials, specifically BCC iron, advancing magnetoelastic modeling for device design.

Contribution

It introduces new atomistic simulation methods to accurately model magnetoelastic effects on sound velocity in ferromagnetic materials.

Findings

Good agreement with the Simon effect including high order terms

Extraction of morphic coefficients for transverse and longitudinal waves

Advancement in magnetoelastic modeling capabilities

Abstract

In this work, we leverage atomistic spin-lattice simulations to examine how magnetic interactions impact the propagation of sound waves through a ferromagnetic material. To achieve this, we characterize the sound wave velocity in BCC iron, a prototypical ferromagnetic material, using three different approaches that are based on the oscillations of kinetic energy, finite-displacement derived forces, and corrections to the elastic constants, respectively. Successfully applying these methods within the spin-lattice framework, we find good agreement with the Simon effect including high order terms. In analogy to experiments, morphic coefficients associated with the transverse and longitudinal waves propagating along the [001] direction are extracted from fits to the fractional change in velocity data. The present efforts represent an advancement in magnetoelastic modelling capabilities which can expedite the design of future magneto-acoustic devices.