Atomically Thin Kagome-Structured Co9Te16 Achieved through Self-Intercalation and Its Flat Band Visualization

• Published in: Nano letters Vol. 24; no. 25; pp. 7672 - 7680
• Main Authors: Wu, Qilong, Quan, Wenzhi, Pan, Shuangyuan, Hu, Jingyi, Zhang, Zehui, Wang, Jian, Zheng, Feipeng, Zhang, Yanfeng
• Format: Journal Article
• Language: English
• Published: American Chemical Society 26.06.2024
• Subjects: kagome lattice; density functional theory calculations; Co9Te16; scanning tunneling microscopy/spectroscopy; flat band
• ISSN: 1530-6984; 1530-6992; 1530-6992
• DOI: 10.1021/acs.nanolett.4c01526

Kagome materials have recently garnered substantial attention due to the intrinsic flat band feature and the stimulated magnetic and spin-related many-body physics. In contrast to their bulk counterparts, two-dimensional (2D) kagome materials feature more distinct kagome bands, beneficial for exploring novel quantum phenomena. Herein, we report the direct synthesis of an ultrathin kagome-structured Co-telluride (Co9Te16) via a molecular beam epitaxy (MBE) route and clarify its formation mechanism from the Co-intercalation in the 1T-CoTe2 layers. More significantly, we unveil the flat band states in the ultrathin Co9Te16 and identify the real-space localization of the flat band states by in situ scanning tunneling microscopy/spectroscopy (STM/STS) combined with first-principles calculations. A ferrimagnetic order is also predicted in kagome-Co9Te16. This work should provide a novel route for the direct synthesis of ultrathin kagome materials via a metal self-intercalation route, which should shed light on the exploration of the intriguing flat band physics in the related systems.