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arXiv · 2306.05634

Realization of a two-dimensional checkerboard lattice in monolayer Cu$_2$N

Xuegao Hu·Run-Wu Zhang·Da-Shuai Ma·Zhihao Cai·Daiyu Geng·Zhenyu Sun·Qiaoxiao Zhao·Jisong Gao·Peng Cheng·Lan Chen·Kehui Wu·Yugui Yao·Baojie Feng
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Abstract

Two-dimensional checkerboard lattice, the simplest line-graph lattice, has been intensively studied as a toy model, while material design and synthesis remain elusive. Here, we report theoretical prediction and experimental realization of the checkerboard lattice in monolayer Cu$_2$N. Experimentally, monolayer Cu$_2$N can be realized in the well-known N/Cu(100) and N/Cu(111) systems that were previously mistakenly believed to be insulators. Combined angle-resolved photoemission spectroscopy measurements, first-principles calculations, and tight-binding analysis show that both systems host checkerboard-derived hole pockets near the Fermi level. In addition, monolayer Cu$_2$N has outstanding stability in air and organic solvents, which is crucial for further device applications.

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Xuegao Hu, Run-Wu Zhang, Da-Shuai Ma, Zhihao Cai, Daiyu Geng, Zhenyu Sun, Qiaoxiao Zhao, Jisong Gao, Peng Cheng, Lan Chen, Kehui Wu, Yugui Yao, Baojie Feng. 2023-06-09. Realization of a two-dimensional checkerboard lattice in monolayer Cu$_2$N. https://doi.org/10.1021/acs.nanolett.3c01111

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