Semimetal Na3Bi Thin Film Grown on Double-Layer Graphene by Molecular Beam Epitaxy
WEN Jing1, GUO Hua1, YAN Chen-Hui1,2, WANG Zhen-Yu1, CHANG Kai1, DENG Peng1, ZHANG Teng1, ZHANG Zhi-Dong2, JI Shuai-Hua1, WANG Li-Li3, HE Ke3, MA Xu-Cun3, CHEN Xi1, XUE Qi-Kun1**
1State Key Laboratory of Low-Dimensional Quantum Physics, Department of Physics, Tsinghua University, Beijing 100084 2Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 3Institute of Physics, Chinese Academy of Sciences, Beijing 100190
Abstract：Atomically flat thin films of topological semimetal Na3Bi are grown on double-layer graphene formed on 6H–SiC(0001) substrates by molecular beam epitaxy. By combined techniques of molecular beam epitaxy, scanning tunneling microscopy and angle resolved photoelectron spectroscopy, the growth conditions for Na3Bi thin films on double-layer graphene are successfully established. The band structure of Na3Bi grown on graphene is mapped along Γ–M and Γ– K directions. Furthermore, the energy band of Na3Bi at higher energy is uncovered by doping Cs atoms on the surface.
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