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arXiv · 1910.00184

Weyl nodes and magnetostructural instability in antiperovskite Mn$_3$ZnC

Samuel M. L. Teicher·Ida K. Svenningsson·Leslie M. Schoop·Ram Seshadri
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Abstract

The ferromagnetic phase of the cubic antiperovskite Mn$_3$ZnC is suggested from first-principles calculation to be a nodal line Weyl semimetal. Features in the electronic structure that are the hallmark of a nodal line Weyl state, a large density of linear band crossings near the Fermi level, can also be interpreted as signatures of a structural and/or magnetic instability. Indeed, it is known that Mn$_3$ZnC undergoes transitions upon cooling from a paramagnetic to a cubic ferromagnetic state under ambient conditions and then further into a non-collinear ferrimagnetic tetragonal phase at a temperature between 250$\,$K and 200$\,$K. The existence of Weyl nodes and their destruction via structural and magnetic ordering is likely to be relevant to a range of magnetostructurally coupled materials.

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Samuel M. L. Teicher, Ida K. Svenningsson, Leslie M. Schoop, Ram Seshadri. 2019-12-13. Weyl nodes and magnetostructural instability in antiperovskite Mn$_3$ZnC. https://doi.org/10.1063/1.5129689

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