The antiferromagnetic kagome lattice compound FeGe has been revealed to host an emergent charge-density-wave (CDW) state which manifests complex interplay between the spin, charge and lattice degrees of freedom. Here, we present a comprehensive study of the de Haas-van Alphen effect by measuring torque magnetometry under magnetic fields up to 45.2 T to map Fermi surfaces in this unusual CDW state. For field along the $c$ direction, we resolve four cyclotron orbits; the largest one roughly corresponding to the area of the 2$\times$2 folded Brillouin zone. Three smaller orbits are characterized by light effective cyclotron masses range from (0.18-0.30) $m_e$. Angle-resolved measurements identify one Fermi surface segment with weak anisotropy. Combined with band structure calculations, our results suggest that features of unfolded Fermi surfaces are robust against CDW reconstruction, corroborating the novel effect of a short-ranged CDW on the electronic structure.

中文翻译：

---

德哈斯-范阿尔芬效应揭示 Kagome 金属 FeGe 电荷密度波态中展开费米面的证据

研究表明，反铁磁 Kagome 晶格化合物 FeGe 具有突现电荷密度波 (CDW) 态，该态表现出自旋、电荷和晶格自由度之间复杂的相互作用。在这里，我们通过测量高达 45.2 T 的磁场下的扭矩磁力来对德哈斯-范阿尔芬效应进行全面研究，以绘制这种不寻常的 CDW 状态下的费米表面。对于沿$c$方向的场，我们解析出四个回旋轨道；最大的一个大致相当于 2$\times$2 折叠布里渊区的面积。三个较小的轨道的特征是光有效回旋加速器质量范围为 (0.18-0.30) $m_e$。角度分辨测量识别出具有弱各向异性的费米面段。结合能带结构计算，我们的结果表明，展开的费米面的特征对于 CDW 重建具有鲁棒性，证实了短程 CDW 对电子结构的新颖影响。