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arXiv · 2608.23485

Emergent Noncollinearity and Near-Degenerate Magnetic Superlattices in AT6X6 Kagome Metals

Weiyi Xia·Wei-Shen Tee·Peter Minch·Feng Zhang·Cai-Zhuang Wang·Vladimir Antropov
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Abstract

Ferromagnetic AT6X6 Kagome compounds are a popular class of systems in which quantum magnetism with topological features has been observed. These systems allow easy chemical substitution, creating an opportunity to fine-tune their properties. In this paper, we present electronic-structure and magnetic ground-state studies of several AT6X6 compounds with relatively low magnetic-ground-state stability. We find unusual magnetic orderings, including complex spin-spiral states and the formation of magnetic long-range superstructures. While LiFe6Ga6 and TiMn6Ge6 retain collinear AFM ground states with low-energy FM/AFM layer sequences, competing spin-spiral and long-period antiferromagnetic structures in MgFe6Ga6 and a double-spin-spiral ground state in TiFe6Ga6 were determined. Magnetism in all these systems appears local, with adiabatic energy profiles suggesting non-Heisenberg long-range interactions, including a strong biquadratic term. In TiMn6Ge6, we found the conditions for magnetic tunneling. Our results show that, in addition to traditional magnetic topological features in such FM Kagome systems, near-degenerate magnetic superstructures suitable for spintronic switching applications can form naturally. Overall, these systems represent a potentially rich playground for neutron diffraction and spintronics experimental studies.

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Weiyi Xia, Wei-Shen Tee, Peter Minch, Feng Zhang, Cai-Zhuang Wang, Vladimir Antropov. 2026-08-24. Emergent Noncollinearity and Near-Degenerate Magnetic Superlattices in AT6X6 Kagome Metals. https://arxiv.org/abs/2608.23485

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