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arXiv · 2310.06909

Fragility of the magnetic order in the prototypical altermagnet RuO$_2$

Andriy Smolyanyuk·Igor I. Mazin·Laura Garcia-Gassull·Roser Valentí
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Abstract

Altermagnetism is a topic that has lately been gaining attention and the RuO$_2$ compound is among one of the most studied altermagnetic candidates. However, the survey of available literature on RuO$_2$ properties suggests that there is no consensus about the magnetism of this material. By performing density functional theory calculations, we show that the electronic properties of stoichiometric RuO$_2$ are described in terms of a smaller Hubbard $U$ within DFT+$U$ than the value required to have magnetism. We further argue that Ru vacancies can actually aid the formation of a magnetic state in RuO$_2$. This in turn suggests that a characterization of the amount of Ru vacancies in experimental samples might help the resolution of the controversy between the different experimental results.

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Andriy Smolyanyuk, Igor I. Mazin, Laura Garcia-Gassull, Roser Valentí. 2023-10-10. Fragility of the magnetic order in the prototypical altermagnet RuO$_2$. https://doi.org/10.1103/physrevb.109.134424

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