Realization of semiconducting Cu_(2)Se by direct selenization of Cu(111)  

作　　者：Yumu Yang Qilong Wu Jiaqi Deng Jing Wang Yu Xia Xiaoshuai Fu Qiwei Tian Li Zhang Long-Jing Yin Yuan Tian Sheng-Yi Xie Lijie Zhang Zhihui Qin 杨雨沐;吴奇龙;邓嘉琦;王静;夏雨;富晓帅;田麒玮;张力;殷隆晶;田园;谢声意;张利杰;秦志辉(Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education&Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices,School of Physics and Electronics,Hunan University,Changsha 410082,China)

机构地区：[1]Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education&Hunan Provincial Key Laboratory of Low-Dimensional Structural Physics and Devices,School of Physics and Electronics,Hunan University,Changsha 410082,China

出　　处：《Chinese Physics B》2021年第11期112-116,共5页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.51772087,11904094,51972106,and 11804089);the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB30000000);Natural Science Foundation of Hunan Province,China(Grant Nos.2019JJ50034 and 2019JJ50073).

摘　　要：Bulk group IB transition-metal chalcogenides have been widely explored due to their applications in thermoelectrics.However,a layered two-dimensional form of these materials has been rarely reported.Here,we realize semiconducting Cu_(2)Se by direct selenization of Cu(111).Scanning tunneling microcopy measurements combined with first-principles calculations allow us to determine the structural and electronic properties of the obtained structure.X-ray photoelectron spectroscopy data reveal chemical composition of the sample,which is Cu_(2)Se.The observed moire pattern indicates a lattice mismatch between Cu_(2)Se and the underlying Cu(111)-√3×√3 surface.Differential conductivity obtained by scanning tunneling spectroscopy demonstrates that the synthesized Cu_(2)Se exhibits a band gap of 0.78 eV.Furthermore,the calculated density of states and band structure demonstrate that the isolated Cu_(2)Se is a semiconductor with an indirect band gap of-0.8 eV,which agrees quite well with the experimental results.Our study provides a simple pathway varying toward the synthesis of novel layered 2D transition chalcogenides materials.

关 键 词：Cu_(2)Se scanning tunneling microscopy scanning tunneling spectroscopy SEMICONDUCTING SELENIZATION 

分 类 号：O469[理学—凝聚态物理]