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arXiv · 2307.03776

Double-$Q$ chiral stripe order in the anomalous Hall antiferromagnet CoNb$_3$S$_6$

Ben Zager·Shang-Shun Zhang·Hana Schiff·Raymond Fan·Paul Steadman·Cristian Batista·Kemp Plumb
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Abstract

We present fine momentum space resolution resonant elastic x-ray scattering measurements of the magnetic structure of the metallic antiferromagnet CoNb$_3$S$_6$. Using circular dichroism and full linear polarization analysis of the magnetic scattering, we reveal a non-coplanar double-$Q$ ($2Q$) order, with a non-collinear commensurate component and a long-wavelength incommensurate helical component. This $2Q$ structure exhibits a staggered scalar spin chirality that forms a modulated stripe-like pattern with no uniform component. This novel magnetic order is naturally explained by the presence of four-spin exchange interactions and exhibits a complex domain structure that suggests a lowering of the structural symmetry. A symmetry analysis indicates that the $2Q$ order enables a finite anomalous Hall effect in CoNb$_3$S$_6$. In addition to identifying a novel type of magnetic ordering and its origin, our results provide insight into the mechanism of the unconventional magnetotransport phenomena in CoNb$_3$S$_6$ and thus identifies potential routes for realizing novel electronic phenomena in metallic antiferromagnets.

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Ben Zager, Shang-Shun Zhang, Hana Schiff, Raymond Fan, Paul Steadman, Cristian Batista, Kemp Plumb. 2023-07-07. Double-$Q$ chiral stripe order in the anomalous Hall antiferromagnet CoNb$_3$S$_6$. https://doi.org/10.1103/5n6h-1wp3

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