The Einstein-de Haas effect in an Fe₁₅ cluster
File(s)Wells_2023_J._Phys. _Condens._Matter_35_495804.pdf (6.33 MB)
Published version
Author(s)
Wells, Tomos
Foulkes, William
Dudarev, Sergei
Horsfield, Andrew H
Type
Journal Article
Abstract
Classical models of spin-lattice coupling are at present unable to accurately reproduce results for numerous properties of ferromagnetic materials, such as heat transport coefficients or the sudden collapse of the magnetic moment in hcp-Fe under pressure. This failure has been attributed to the absence of a proper treatment of effects that are inherently quantum mechanical in nature, notably spin-orbit coupling. This paper introduces a time-dependent, non-collinear tight binding model, complete with spin-orbit coupling and vector Stoner exchange terms, that is capable of simulating the Einstein-de Haas effect in a ferromagnetic Fe15 cluster. The tight binding model is used to investigate the adiabaticity timescales that determine the response of the orbital and spin angular momenta to a rotating, externally applied Β field, and we show that the qualitative behaviours of our simulations can be extrapolated to realistic timescales by use of the adiabatic theorem.
An analysis of the trends in the torque contributions with respect to the field strength demonstrates that SOC is necessary to observe a transfer of angular momentum from the electrons to the nuclei at experimentally realistic Β fields.
The simulations presented in this paper demonstrate the Einstein-de Haas effect from first principles using a Fe cluster.
Date Issued
2023-12-11
Date Acceptance
2023-08-11
Citation
Journal of Physics: Condensed Matter, 2023, 35 (49), pp.1-16
ISSN
0953-8984
Publisher
IOP Publishing
Start Page
1
End Page
16
Journal / Book Title
Journal of Physics: Condensed Matter
Volume
35
Issue
49
Copyright Statement
© 2023 The Author(s). Published by IOP Publishing Ltd. As the Version of Record of this article is going to be / has been published on a gold open access basis under a CC BY 4.0 licence, this Accepted Manuscript is available for reuse under a CC BY 4.0 licence immediately.
License URL
Identifier
https://iopscience.iop.org/article/10.1088/1361-648X/acef9b
Publication Status
Published
Article Number
495804
Date Publish Online
2023-09-13