Kagome metal consists of a two-dimensional corner-sharing triangle network of atoms. This geometrical arrangement has been proposed to generate an electronic flat band, a promising platform to engineer interactions in materials and drive emergent quantum phenomena. In particular, recent observation of lattice-derived flat bands in transition metal based kagome metals has ignited great interest in designing generalized lattice models that can universally produce stable flat bands [1]. In the presentation, I will introduce our recent efforts to stabilize kagome metals in thin film form by means of molecular beam epitaxy and explore the unique physics therein. By combining high quality thin film synthesis and planar tunneling spectroscopy, we show that the two-dimensional flat band is realized and localized at the interface between binary kagome metal FeSn and semiconducting doped SrTiO3, providing a potential platform for electronic devices that facilitate manipulation of electronic properties unique to flat bands [2,3]. More broadly, the results propose a new design principle that interfacing two distinct materials offer an alternate pathway to artificially stabilizing correlated flat bands.
 

[1] M. Kang et al., Nat. Mater. 19, 163 (2020).
[2] H. Inoue and M. Hang et al., Appl. Phys. Lett. 115, 072403 (2019).
[3] M. Hang and H. Inoue et al., Nat. Commun. 12, 5345 (2021). 
 

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