Pan Zemin, Xiong Wenqi, Dai Jiaqi, Zhang Hui, Wang Yunhua, Jian Tao, Cui Xingxia, Deng Jinghao, Lin Xiaoyu, Cheng Zhengbo, Bai Yusong, Zhu Chao, Huo Da, Li Geng, Feng Min, He Jun, Ji Wei, Yuan Shengjun, Wu Fengcheng, Zhang Chendong, Gao Hong-Jun
School of Physics and Technology, Wuhan University, Wuhan, China.
Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-nano Devices, School of Physics, Renmin University of China, Beijing, China.
Nat Commun. 2025 Mar 31;16(1):3084. doi: 10.1038/s41467-025-58226-2.
Although the kagome model is fundamentally two-dimensional, the essential kagome physics, i.e., the kagome-bands-driven emergent electronic states, has yet to be explored in the monolayer limit. Here, we present the experimental realization of kagome physics in monolayer MoTe, showcasing both ferromagnetic ordering and a correlated insulating state with an energy gap of up to 15 meV. Using a combination of scanning tunnelling microscopy and theoretical calculations, we find a structural phase of the monolayer Mo-Te compound, which forms a mirror-twin boundary loop superlattice exhibiting kagome geometry and multiple sets of kagome bands. The partial occupancy of these nearly flat bands results in Fermi surface instability, counteracted by the emergence of ferromagnetic order (with a coercive field ~0.1 T, as observed by spin-polarized STM) and the opening of a correlated hard gap. Our work establishes a robust framework featuring well-defined atomic and band structures, alongside the intrinsic two-dimensional nature, essential for the rigorous examination of kagome physics.
尽管 Kagome 模型本质上是二维的，但在单层极限情况下，尚未对其基本的 Kagome 物理特性，即由 Kagome 能带驱动的新兴电子态进行探索。在此，我们展示了单层 MoTe₂ 中 Kagome 物理特性的实验实现，呈现出铁磁有序以及高达 15 meV 的能隙的关联绝缘态。通过结合扫描隧道显微镜和理论计算，我们发现了单层 Mo-Te 化合物的一种结构相，它形成了具有 Kagome 几何形状和多组 Kagome 能带的镜面对称孪晶边界环超晶格。这些近平坦能带的部分占据导致费米面不稳定，而铁磁序的出现（自旋极化 STM 观测到的矫顽场约为 0.1 T）和关联硬能隙的打开抵消了这种不稳定性。我们的工作建立了一个强大的框架，其具有明确的原子和能带结构，以及对于严格研究 Kagome 物理特性至关重要的固有二维特性。
