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arXiv · 2411.14415

Ground-state magnetic structures of topological kagome metals RV$_6$Sn$_6$ (R = Tb, Dy, Ho, Er)

Abstract

Magnetic kagome metals have attracted tremendous research interests recently, because they represent an ideal playground for exploring the fascinating interplay between their intrinsically inherited topologically non-trivial electron band structures, magnetism and electronic correlation effects, and the resultant novel electronic/magnetic states and emergent excitations. In this work, we report a comprehensive single-crystal neutron diffraction investigation of the ground-state magnetic structures of the recently discovered V-based topological kagome metals RV$_6$Sn$_6$ (R = Tb, Dy, Ho, Er). Furthermore, the sample synthesis details and our systematic studies of crystal structure, low-temperature magnetic and thermodynamic properties of these compounds via various in-house characterization techniques are also reported. It can be revealed that RV$_6$Sn$_6$ (R = Tb, Dy, Ho) have a collinear ferromagnetic order in the ground state, with the ordered magnetic moment aligned along the c axis for R = Tb, Ho, while approximately 20${^\circ}$ tilted off from the c axis for R = Dy. In contrast, ErV$_6$Sn$_6$ shows an A-type antiferromagnetic structure with a magnetic propagation vector k = (0, 0, 0.5), and with the ordered magnetic moment aligned in the ab plane. A comparison of the low-temperature magnetic structures for both the extensively investigated topological kagome metal series of RV$_6$Sn$_6$ and RMn$_6$Sn$_6$ is given in details. This allows to gain new insights into the complex magnetic interactions, diverse single-ion magnetic anisotropies and spin dynamics in these compounds. The reported ground-state magnetic structures in RV$_6$Sn$_6$ (R = Tb, Dy, Ho, Er) can pave the way for further explorations of the possible interplay between magnetism and topologically non-trivial electron band structures in the magnetically ordered phase regime.

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Yishui Zhou, Min-Kai Lee, Sabreen Hammouda, Sheetal Devi, Shin-Ichiro Yano, Romain Sibille, Oksana Zaharko, Wolfgang Schmidt, Karin Schmalzl, Ketty Beauvois, Eric Ressouche, Po-Chun Chang, Chun-Hao Huang, Lieh-Jeng Chang, Thomas Brückel, Yixi Su. 2024-11-21. Ground-state magnetic structures of topological kagome metals RV$_6$Sn$_6$ (R = Tb, Dy, Ho, Er). https://doi.org/10.1103/physrevresearch.6.043291

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