Yin Jia-Xin, Jiang Yu-Xiao, Teng Xiaokun, Hossain Md Shafayat, Mardanya Sougata, Chang Tay-Rong, Ye Zijin, Xu Gang, Denner M Michael, Neupert Titus, Lienhard Benjamin, Deng Han-Bin, Setty Chandan, Si Qimiao, Chang Guoqing, Guguchia Zurab, Gao Bin, Shumiya Nana, Zhang Qi, Cochran Tyler A, Multer Daniel, Yi Ming, Dai Pengcheng, Hasan M Zahid
Laboratory for Topological Quantum Matter and Advanced Spectroscopy (B7), Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
Department of Physics and Astronomy, Rice Center for Quantum Materials, Rice University, Houston, Texas 77005, USA.
Phys Rev Lett. 2022 Oct 14;129(16):166401. doi: 10.1103/PhysRevLett.129.166401.
Kagome materials often host exotic quantum phases, including spin liquids, Chern gap, charge density wave, and superconductivity. Existing scanning microscopy studies of the kagome charge order have been limited to nonkagome surface layers. Here, we tunnel into the kagome lattice of FeGe to uncover features of the charge order. Our spectroscopic imaging identifies a 2×2 charge order in the magnetic kagome lattice, resembling that discovered in kagome superconductors. Spin mapping across steps of unit cell height demonstrates the existence of spin-polarized electrons with an antiferromagnetic stacking order. We further uncover the correlation between antiferromagnetism and charge order anisotropy, highlighting the unusual magnetic coupling of the charge order. Finally, we detect a pronounced edge state within the charge order energy gap, which is robust against the irregular shape fluctuations of the kagome lattice edges. We discuss our results with the theoretically considered topological features of the kagome charge order including unconventional magnetism and bulk-boundary correspondence.
Kagome材料常常呈现出奇异的量子相，包括自旋液体、陈数能隙、电荷密度波和超导性。现有的关于Kagome电荷序的扫描显微镜研究仅限于非Kagome表面层。在此，我们深入FeGe的Kagome晶格以揭示电荷序的特征。我们的光谱成像识别出磁性Kagome晶格中的2×2电荷序，类似于在Kagome超导体中发现的电荷序。跨越晶胞高度台阶的自旋映射表明存在具有反铁磁堆叠顺序的自旋极化电子。我们进一步揭示了反铁磁性与电荷序各向异性之间的相关性，突出了电荷序的异常磁耦合。最后，我们在电荷序能隙内检测到一个明显的边缘态，它对Kagome晶格边缘的不规则形状波动具有鲁棒性。我们将我们的结果与理论上考虑的Kagome电荷序的拓扑特征进行了讨论，包括非常规磁性和体-边界对应关系。
