Theoretical Understanding of the Kagome-Honeycomb Lateral Heterostructure in FeSn

Lateral heterostructures offer spatially resolved property control, enabling the integration of dissimilar materials and promoting novel phenomena not typically observed in vertical heterostructures. Using the first-principles density functional theory approach, we investigate the stability and electronic structures of lateral heterointerfaces in FeSn containing Kagome and honeycomb layers. We provide a comprehensive understanding of the bonding motif connecting the Fe₃Sn-terminated Kagome and Sn₂-terminated honeycomb surfaces. More importantly, we reveal a unique distance-dependent evolution of the electronic states in the vicinity of the heterointerfaces. This evolution is significantly influenced by the orbital character of the flat bands. Our findings are consistent with the scanning tunneling microscopy/spectroscopy studies on the Kgome-honeycomb lateral heterostructure sample made with molecular beam epitaxy technique. It offers a new perspective for modulating the electronic properties of the Kagome lattice, which should be beneficial for the development of future quantum devices.