,Epitaxial growth and air-stability of monolayer Cu2Te

• 作 者: K Qian L Gao H Li S Zhang J H Yan C Liu J O Wang T Qian H Ding Y Y Zhang X Lin S X Du H-J Gao
• 机 构: Institute of Physics&University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing
• 出 处: 中国物理B（英文版）
• 发表日期: 2020年1期
• 关键词: cuprous telluride (Cu2Te) scanning tunneling microscopy (STM) density functional

A new two-dimensional atomic crystal, monolayer cuprous telluride (Cu2Te) has been fabricated on a graphene-SiC(0001) substrate by molecular beam epitaxy (MBE). The low-energy electron diffraction (LEED) characterization shows that the monolayer Cu2Te forms a√3×√3 superstructure with respect to the graphene substrate. The atomic structure of the monolayer Cu2Te is investigated through a combination of scanning tunneling microscopy (STM) experiments and density functional theory (DFT) calculations. The stoichiometry of the Cu2Te sample is verified by x-ray photoelectron spectroscopy (XPS) measurement. The angle-resolved photoemission spectroscopy (ARPES) data present the electronic band structure of the sample, which is in good agreement with the calculated results. Furthermore, air-exposure experiments reveal the chemical stability of the monolayer Cu2Te. The fabrication of this new 2D material with a particular structure may bring new physical properties for future applications.