A new two-dimensional atomic crystal, monolayer cuprous telluride(Cu2Te) has been fabricated on a grapheneSi C(0001) substrate by molecular beam epitaxy(MBE). The low-energy electron diffraction(LEED) characte...A new two-dimensional atomic crystal, monolayer cuprous telluride(Cu2Te) has been fabricated on a grapheneSi C(0001) substrate by molecular beam epitaxy(MBE). The low-energy electron diffraction(LEED) characterization shows that the monolayer Cu2Te forms ■ 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.展开更多
基金Project supported by the National Key Research&Development Program of China(Grant Nos.2016YFA0202300 and 2018YF A0305800)the National Natural Science Foundation of China(Grant Nos.61888102,11604373,61622116,and 51872284)+2 种基金the CAS Pioneer Hundred Talents Program,China,the Strategic Priority Research Program of Chinese Academy of Sciences(Grant Nos.XDB30000000 and XDB28000000)Beijing Nova Program,China(Grant No.Z181100006218023)the University of Chinese Academy of Sciences
文摘A new two-dimensional atomic crystal, monolayer cuprous telluride(Cu2Te) has been fabricated on a grapheneSi C(0001) substrate by molecular beam epitaxy(MBE). The low-energy electron diffraction(LEED) characterization shows that the monolayer Cu2Te forms ■ 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.