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arXiv · 1904.12176

Complex magnetism of B20-MnGe: from spin-spirals, hedgehogs to monopoles

Marcel Bornemann·Sergii Grytsiuk·Paul F. Baumeister·Manuel dos Santos Dias·Rudolf Zeller·Samir Lounis·Stefan Blügel
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Abstract

B20 compounds are the playground for various non-trivial magnetic textures such as skyrmions, which are topologically protected states. Recent measurements on B20-MnGe indicate no clear consensus on its magnetic behavior, which is characterized by the presence of either spin-spirals or 3-dimensional objects interpreted to be a cubic lattice of hedgehogs and anti-hedgehogs. Utilizing a massively parallel linear scaling all-electron density functional algorithm, we find from full first-principles simulations on cells containing thousands of atoms that upon increase of the compound volume, the state with lowest energy switches across different magnetic phases: ferromagnetic, spin-spiral, hedgehog and monopole.

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Marcel Bornemann, Sergii Grytsiuk, Paul F. Baumeister, Manuel dos Santos Dias, Rudolf Zeller, Samir Lounis, Stefan Blügel. 2019-04-27. Complex magnetism of B20-MnGe: from spin-spirals, hedgehogs to monopoles. https://doi.org/10.1088/1361-648x%2Fab38a0

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