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arXiv · 1805.09372

Gradual pressure-induced change in the magnetic structure of the non-collinear antiferromagnet Mn$_3$Ge

A. S. Sukhanov·Sanjay Singh·L. Caron·Th. Hansen·A. Hoser·V. Kumar·H. Borrmann·A. Fitch·P. Devi·K. Manna·C. Felser·D. S. Inosov
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Abstract

By means of powder neutron diffraction we investigate changes in the magnetic structure of the coplanar non-collinear antiferromagnet Mn$_3$Ge caused by an application of hydrostatic pressure up to 5\phantom{ }GPa. At ambient conditions the kagom\'e layers of Mn atoms in Mn$_3$Ge order in a triangular 120$^{\circ}$ spin structure. Under high pressure the spins acquire a uniform out-of-plane canting, gradually transforming the magnetic texture to a non-coplanar configuration. With increasing pressure the canted structure fully transforms into the collinear ferromagnetic one. We observed that magnetic order is accompanied by a noticeable magnetoelastic effect, namely, spontaneous magnetostriction. The latter induces an in-plane magnetostrain of the hexagonal unit cell at ambient pressure and flips to an out-of-plane strain at high pressures in accordance with the change of the magnetic structure.

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A. S. Sukhanov, Sanjay Singh, L. Caron, Th. Hansen, A. Hoser, V. Kumar, H. Borrmann, A. Fitch, P. Devi, K. Manna, C. Felser, D. S. Inosov. 2018-05-23. Gradual pressure-induced change in the magnetic structure of the non-collinear antiferromagnet Mn$_3$Ge. https://doi.org/10.1103/physrevb.97.214402

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