New Publication: Atomistic simulations of magnetoelastic effects on sound velocity

The Nuclear Futures Institute is pleased to announce that Dr Alberto Fraile of the Materials research group has recently published a recent paper in the Physical Review B journal as one of four co-authors. The journal covers condensed matter physics and materials physics.

Physical Review B (PRB) is the world’s largest dedicated physics journal, publishing approximately 100 new, high-quality papers each week. 

Novel magnetoacoustic phenomena have been discovered in recent years, such as acoustic spin pumping and magnetization switching induced by sound waves, with potential technological applications in spintronics and magnetic recording. 

Atomistic simulations of magnetic effects on sound waves were especially challenging until recently. This phenomenon involves coupled dynamics of magnetic moments and atoms, so it is not possible to use only standard atomistic spin dynamics (SD) or molecular dynamics (MD) since the motion of atoms or spins are neglected, respectively. An alternative approach could be to combine spin-polarized ab-inito molecular dynamics and SD. This strategy is very accurate but unfortunately is quite demanding computationally, so that it might not a be a convenient method due to the large atomic supercells required to study sound waves.  

To overcome this limitation, one could couple spin dynamics with molecular dynamics (SD-MD), also referred as spin-lattice dynamics, thus enabling the simulation of both large system sizes and time scales. This paper builds on recent advances in atomistic models based on spin-lattice simulations offering the possibility of studying magnetoelastic phenomena computationally. The manuscript describes how their spin-lattice simulations technique finds good agreement with the “Simon effect” including high-order terms for pure iron.


Figure 1 – Initial atomic displacement of a transverse phonon mode propagating in the direction kph∥[001] with polarisation u∥[100] for BCC Fe.

The paper offers an advancement in the magneto-elastic modelling capabilities of today, including the design of future magneto-acoustic devices such as speakers and microphones.

Read the full paper here.