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arXiv · 2009.06880

Zero-field magnetic ground state of EuMg$_2$Bi$_2$

Santanu Pakhira·Thomas Heitmann·S. X. M. Riberolles·B. G. Ueland·R. J. McQueeney·D. C. Johnston·David Vaknin
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Abstract

Layered trigonal EuMg$_2$Bi$_2$ is reported to be a topological semimetal that hosts multiple Dirac points that may be gapped or split by the onset of magnetic order. Here, we report zero-field single-crystal neutron-diffraction and bulk magnetic susceptibility measurements versus temperature $\chi(T)$ of EuMg$_2$Bi$_2$ that show the intraplane ordering is ferromagnetic (Eu$^{2+},\, S= 7/2$) with the moments aligned in the $ab$-plane while adjacent layers are aligned antiferromagnetically (i.e., A-type antiferromagnetism) below the N\'eel temperature.

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Santanu Pakhira, Thomas Heitmann, S. X. M. Riberolles, B. G. Ueland, R. J. McQueeney, D. C. Johnston, David Vaknin. 2020-09-15. Zero-field magnetic ground state of EuMg$_2$Bi$_2$. https://doi.org/10.1103/physrevb.103.024408

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