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arXiv · 2011.06351

Short period magnetization texture of B20-MnGe explained by thermally fluctuating local moments

Eduardo Mendive-Tapia·Manuel dos Santos Dias·Sergii Grytsiuk·Julie B. Staunton·Stefan Blügel·Samir Lounis
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Abstract

B20-type compounds, such as MnSi and FeGe, host helimagnetic and skyrmion phases at the mesoscale, which are canonically explained by the combination of ferromagnetic isotropic interactions with weaker chiral Dzyaloshinskii-Moriya ones. Mysteriously, MnGe evades this paradigm as it displays a noncollinear magnetic state at a much shorter nanometer scale. Here we show that the length scale and volume-dependent magnetic properties of MnGe stem from purely isotropic exchange interactions, generally obtained in the paramagnetic state. Our approach is validated by comparing MnGe with the canonical B20-helimagnet FeGe. The free energy of MnGe is calculated, from which we show how triple-q magnetic states can stabilize by adding higher-order interactions.

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Eduardo Mendive-Tapia, Manuel dos Santos Dias, Sergii Grytsiuk, Julie B. Staunton, Stefan Blügel, Samir Lounis. 2021-01-12. Short period magnetization texture of B20-MnGe explained by thermally fluctuating local moments. https://doi.org/10.1103/physrevb.103.024410

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