Yan Linghao, Silveira Orlando J, Alldritt Benjamin, Kezilebieke Shawulienu, Foster Adam S, Liljeroth Peter
Department of Applied Physics, Aalto University, 00076 Aalto, Finland.
Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
ACS Nano. 2021 Nov 23;15(11):17813-17819. doi: 10.1021/acsnano.1c05986. Epub 2021 Nov 3.
The combination of two-dimensional (2D) materials into vertical heterostructures has emerged as a promising path to designer quantum materials with exotic properties. Here, we extend this concept from inorganic 2D materials to 2D metal-organic frameworks (MOFs) that offer additional flexibility in realizing designer heterostructures. We successfully fabricate a monolayer 2D Cu-dicyanoanthracene MOF on a 2D van der Waals NbSe superconducting substrate. The structural and electronic properties of two different phases of the 2D MOF are characterized by low-temperature scanning tunneling microscopy (STM) and spectroscopy (STS), complemented by density-functional theory (DFT) calculations. These experiments allow us to follow the formation of the kagome band structure from Star of David-shaped building blocks. This work extends the synthesis and electronic tunability of 2D MOFs beyond the electronically less relevant metal and semiconducting surfaces to superconducting substrates, which are needed for the development of emerging quantum materials such as topological superconductors.
将二维（2D）材料组合成垂直异质结构已成为制备具有奇异特性的定制量子材料的一条有前景的途径。在此，我们将这一概念从无机二维材料扩展到二维金属有机框架（MOF），后者在实现定制异质结构方面提供了额外的灵活性。我们成功地在二维范德华NbSe超导衬底上制备了单层二维Cu - 二氰基蒽MOF。二维MOF的两个不同相的结构和电子性质通过低温扫描隧道显微镜（STM）和能谱（STS）进行表征，并辅以密度泛函理论（DFT）计算。这些实验使我们能够追踪由大卫之星形状的构建块形成的 Kagome 能带结构。这项工作将二维MOF的合成和电子可调性从电子相关性较低的金属和半导体表面扩展到超导衬底，而超导衬底是诸如拓扑超导体等新兴量子材料发展所必需的。
