Realization of a Two-Dimensional Checkerboard Lattice in Monolayer Cu2N

• DOI: 10.1021/acs.nanolett.3c01111
• Publication Date: 2023-06-15T22:25:06Z
• Authors: 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
• Keywords: Condensed Matter - Materials Science; Materials Science (cond-mat.mtrl-sci); FOS: Physical sciences; Computational Physics (physics.comp-ph); Physics - Computational Physics

Nano Letters, in press<br/>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.<br/>