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arXiv · 2001.02601

Ground state magnetic structure of Mn$_3$Ge

J. -R. Soh·F. de Juan·N. Qureshi·H. Jacobsen·H. -Y. Wang·Y. -F. Guo·A. T. Boothroyd
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Abstract

We have used spherical neutron polarimetry to investigate the magnetic structure of the Mn spins in the hexagonal semimetal Mn$_3$Ge, which exhibits a large intrinsic anomalous Hall effect. Our analysis of the polarimetric data finds a strong preference for a spin structure with $E_{1g}$ symmetry relative to the $D_{6h}$ point group. We show that weak ferromagnetism is an inevitable consequence of the symmetry of the observed magnetic structure, and that sixth order anisotropy is needed to select a unique ground state.

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J. -R. Soh, F. de Juan, N. Qureshi, H. Jacobsen, H. -Y. Wang, Y. -F. Guo, A. T. Boothroyd. 2020-01-08. Ground state magnetic structure of Mn$_3$Ge. https://doi.org/10.1103/physrevb.101.140411

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