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arXiv · 2201.10368

Atomistic simulations of magnetoelastic effects on sound velocity

P. Nieves·J. Tranchida·S. Nikolov·A. Fraile·D. Legut
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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.

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P. Nieves, J. Tranchida, S. Nikolov, A. Fraile, D. Legut. 2022-01-25. Atomistic simulations of magnetoelastic effects on sound velocity. https://doi.org/10.1103/physrevb.105.134430

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