AI 中文总结
本文对多种AT6X6 Kagome金属的电子结构与磁基态开展研究，发现其存在异常磁有序及非海森堡长程相互作用，还确定了适用于自旋电子学开关的近简并磁性超结构，为相关实验研究提供了丰富平台。
AI 中文摘要
铁磁性AT6X6 Kagome化合物是一类热门体系，已在其中观测到具有拓扑特征的量子磁性。这类体系易于进行化学取代，为精细调控其性质提供了机会。本文对几种磁基态稳定性相对较低的AT6X6化合物开展电子结构与磁基态研究，发现了包括复杂自旋螺旋态和磁性长程超结构形成在内的异常磁有序。LiFe6Ga6和TiMn6Ge6保持共线反铁磁（AFM）基态，具有低能铁磁（FM）/AFM层序列；而MgFe6Ga6中存在竞争的自旋螺旋和长周期反铁磁结构，TiFe6Ga6中则确定存在双自旋螺旋基态。所有这些体系中的磁性均呈现局域性，绝热能量分布表明存在非海森堡长程相互作用，包括强双二次项；在TiMn6Ge6中，还发现了磁隧穿的条件。研究结果表明，除了这类铁磁Kagome体系中传统的磁性拓扑特征外，还可自然形成适用于自旋电子学开关应用的近简并磁性超结构，总体而言，这类体系有望成为中子衍射和自旋电子学实验研究的丰富平台。
英文摘要
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.
