Yang R, Corasaniti M, Le C C, Liao Z Y, Wang A F, Du Q, Petrovic C, Qiu X G, Hu J P, Degiorgi L
Laboratorium für Festkörperphysik, ETH-Zürich, 8093 Zürich, Switzerland.
Max Planck Institute for Chemical Physics of Solids, Dresden 01187, Germany.
Phys Rev Lett. 2020 Apr 3;124(13):137201. doi: 10.1103/PhysRevLett.124.137201.
The ternary AMnBi_{2} (A is alkaline as well as rare-earth atom) materials provide an arena for investigating the interplay between low-dimensional magnetism of the antiferromagnetic MnBi layers and the electronic states in the intercalated Bi layers, which harbor relativistic fermions. Here, we report on a comprehensive study of the optical properties and magnetic torque response of Ca_{1-x}Na_{x}MnBi_{2}. Our findings give evidence for a spin canting occurring at T_{s}∼50-100 K. With the support of first-principles calculations we establish a direct link between the spin canting and the reconstruction of the electronic band structure, having immediate implications for the spectral weight reshuffling in the optical response, signaling a partial gapping of the Fermi surface, and the dc transport properties below T_{s}.
三元 AMnBi₂（A 为碱金属以及稀土原子）材料为研究反铁磁 MnBi 层的低维磁性与插层 Bi 层中包含相对论费米子的电子态之间的相互作用提供了一个平台。在此，我们报告了对 Ca₁₋ₓNaₓMnBi₂ 的光学性质和磁转矩响应的全面研究。我们的研究结果证明在 Ts ∼ 50 - 100 K 时发生了自旋倾斜。在第一性原理计算的支持下，我们建立了自旋倾斜与电子能带结构重构之间的直接联系，这对光学响应中的光谱权重重新分布、费米面的部分能隙信号以及 Ts 以下的直流输运性质具有直接影响。
