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arXiv · 2211.13486

Influence of non-local damping on magnon properties of ferromagnets

Zhiwei Lu·I. P. Miranda·Simon Streib·Manuel Pereiro·Erik Sjöqvist·Olle Eriksson·Anders Bergman·Danny Thonig·Anna Delin
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Abstract

We study the influence of non-local damping on magnon properties of Fe, Co, Ni and Fe$_{1-x}$Co$_{x}$ ($x=30\%,50\%$) alloys. The Gilbert damping parameter is typically considered as a local scalar both in experiment and in theoretical modelling. However, recent works have revealed that Gilbert damping is a non-local quantity that allows for energy dissipation between atomic sites. With the Gilbert damping parameters calculated from a state-of-the-art real-space electronic structure method, magnon lifetimes are evaluated from spin dynamics and linear response, where a good agreement is found between these two methods. It is found that non-local damping affects the magnon lifetimes in different ways depending on the system. Specifically, we find that in Fe, Co, and Ni the non-local damping decreases the magnon lifetimes, while in $\rm Fe_{70}Co_{30}$ and Fe$_{50}$Co$_{50}$ an opposite, non-local damping effect is observed, and our data show that it is much stronger in the former.

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Zhiwei Lu, I. P. Miranda, Simon Streib, Manuel Pereiro, Erik Sjöqvist, Olle Eriksson, Anders Bergman, Danny Thonig, Anna Delin. 2022-11-24. Influence of non-local damping on magnon properties of ferromagnets. https://doi.org/10.1103/physrevb.108.014433

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