Anisotropic mesoscale magnetic scattering across the spin-reorientation transition in TbMn6Sn6

Zhuang Xu; Fan Chen; Hui Cheng; Xinmin Wang; Taisen Zuo; He Cheng; Haitao Hu; Cuiping Zhang; Qian Zhao; Michel Kenzelmann; Jonathan S. White; Junying Shen; Xin Tong

arXiv · 2610.04903

Anisotropic mesoscale magnetic scattering across the spin-reorientation transition in TbMn6Sn6

Zhuang Xu·Fan Chen·Hui Cheng·Xinmin Wang·Taisen Zuo·He Cheng·Haitao Hu·Cuiping Zhang·Qian Zhao·Michel Kenzelmann·Jonathan S. White·Junying Shen·Xin Tong

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Abstract

TbMn6Sn6 is a centrosymmetric ferrimagnetic kagome metal that combines topological electronic states with strong magnetic anisotropy and a near-room-temperature spin-reorientation transition (SRT). Real-space imaging studies of thin specimens have revealed helical stripes, biskyrmion-like textures, and skyrmion-bubble-like structures in the spin-reorientation regime. Whether such local textures develop into a bulk long-range-ordered skyrmion lattice remains unresolved. Here we present small-angle neutron scattering (SANS) results probing the mesoscale magnetism of a bulk TbMn6Sn6 single crystal. We observe no sixfold SANS Bragg pattern indicative of a long-range-ordered skyrmion lattice under the explored conditions. Instead, the dominant magnetic response is an anisotropic twofold low-Q scattering component whose intensity distribution and field dependence evolve markedly across the spin-reorientation regime. In zero field, a broad and horizontally elongated low-Q signal develops above TSR and weakens as the system approaches the paramagnetic state. At 345 K with H || b, the signal is diffuse and is suppressed rapidly below about 700 Oe. By contrast, at 310 K with H || c, close to TSR, the response is more concentrated and line-shaped and persists to higher fields. The contrasts between these scans likely reflect the combined effects of rapidly evolving magnetic anisotropy near TSR and the field geometry. Our results therefore establish a bulk anisotropic mesoscale magnetic response across the spin-reorientation regime, consistent with stripe- or domain-related textures reported by real-space imaging, while not uniquely identifying their real-space morphology.

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BibTeX RIS

Zhuang Xu, Fan Chen, Hui Cheng, Xinmin Wang, Taisen Zuo, He Cheng, Haitao Hu, Cuiping Zhang, Qian Zhao, Michel Kenzelmann, Jonathan S. White, Junying Shen, Xin Tong. 2026-10-04. Anisotropic mesoscale magnetic scattering across the spin-reorientation transition in TbMn6Sn6. https://arxiv.org/abs/2610.04903

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