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arXiv · 2411.09300

Large anomalous Hall effect and \textit{A}-phase in hexagonal polar magnet Gd$_3$Ni$_8$Sn$_4$

Arnab Bhattacharya·Afsar Ahmed·Apurba Dutta·Ajay Kumar·Anis Biswas·Yaroslav Mudryk·Indranil Das
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Abstract

While recent theoretical studies have positioned noncollinear polar magnets with $C_{nv}$ symmetry as compelling candidates for realizing topological magnetic phases and substantial intrinsic anomalous Hall conductivity, experimental realizations of the same in strongly correlated systems remain rare. Here, we present a large intrinsic anomalous Hall effect and extended topological magnetic ordering in Gd$_3$Ni$_8$Sn$_4$ with hexagonal $C_{6v}$ symmetry. Observation of topological Hall response, corroborated by metamagnetic anomalies in isothermal magnetization, peak/hump features in field-evolution of ac susceptibility and longitudinal resistivity, attests to the stabilization of skyrmion $A$-phase. The anomalous Hall effect is quantitatively accounted for by the intrinsic Berry curvature-mediated mechanism. Our results underscore polar magnets as a promising platform to investigate a plethora of emergent electrodynamic responses rooted in the interplay between magnetism and topology.

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Arnab Bhattacharya, Afsar Ahmed, Apurba Dutta, Ajay Kumar, Anis Biswas, Yaroslav Mudryk, Indranil Das. 2024-11-14. Large anomalous Hall effect and \textit{A}-phase in hexagonal polar magnet Gd$_3$Ni$_8$Sn$_4$. https://arxiv.org/abs/2411.09300

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