Large anomalous Hall effect induced by local disorder in the kagome ferrimagnet TbMn 6 Sn 6

作者：Quanxing Wei, Zhou Yi, Hengxin Tan, Lingling Gao, Ronghui Liu, Junkai Jing, Yahui Li, Dongyun Chen, Dongyun Chen, Yun‐Ze Long, Yanpeng Qi, Yanpeng Qi, Binghai Yan, Bing Teng, Dong Chen, Dong Chen · 发表于：Physical review. B./Physical review. B · 年份：2025 · DOI：10.1103/physrevb.111.064412 · 被引用次数：7 · 研究领域：Advanced Condensed Matter Physics、Topological Materials and Phenomena、Rare-earth and actinide compounds

The kagome ferrimagnet family $R\mathrm{M}{\mathrm{n}}_{6}{\mathrm{Sn}}_{6}$ ($R$ = Gd - Er) features Chern-gapped Dirac points in the band structure, theoretically allowing a large anomalous Hall effect. However, the experimentally observed anomalous Hall effect in $R\mathrm{M}{\mathrm{n}}_{6}{\mathrm{Sn}}_{6}$ is only comparable to those found in conventional ferromagnets. Here, we report a significant enhancement of anomalous Hall effect in the kagome ferrimagnet ${\mathrm{TbMn}}_{6}{\mathrm{Sn}}_{6}$ induced by local disorder through Mg substitution on Tb. By electrical transport and anomalous Nernst effect measurements, combined with first-principles calculations, we demonstrate that the Mg substitution modulates the band structure of ${\mathrm{TbMn}}_{6}{\mathrm{Sn}}_{6}$, leading to an increase in intrinsic anomalous Hall conductivity. Additionally, the modulated band structure enhances the longitudinal conductivity, further boosting the extrinsic anomalous Hall conductivity dominated by skew scattering. Consequently, the total anomalous Hall conductivity reaches $950\phantom{\rule{0.16em}{0ex}}{\mathrm{\ensuremath{\Omega}}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}\mathrm{c}{\mathrm{m}}^{\ensuremath{-}1}$, entering the regime of topological magnets. Both of the large intrinsic and extrinsic anomalous Hall conductivity can be attributed to the nontrivial band structure near the Fermi level.