Epitaxial growth of antimony nanofilms on HOPG and thermal desorption to control the film thickness

• 作 者: Shuya Xing Le Lei Haoyu Dong Jianfeng Guo Feiyue Cao Shangzhi Gu Sabir Hussain Fei Pang Wei Ji Rui Xu Zhihai Cheng
• 机 构: Beijing Key Laboratory of Optoelectronic Functional Materials & Micro-nano Devices,Department of Phy
• 出 处: 中国物理B（英文版）
• 发表日期: 2020年9期
• 关键词: epitaxial growth antimony films scanning tunneling microscope (STM) thermal deso

Group-V elemental nanofilms were predicted to exhibit interesting physical properties such as nontrivial topological properties due to their strong spin-orbit coupling,the quantum confinement,and surface effect.It was reported that the ultrathin Sb nanofilms can undergo a series of topological transitions as a function of the film thickness h: from a topological semimetal (h ＞ 7.8 nm) to a topological insulator (7.8 nm＞ h ＞ 2.7 nm),then a quantum spin Hall (QSH) phase (2.7 nm ＞ h ＞ 1.0 nm) and a topological trivial semiconductor (h ＜ 1.0 nm).Here,we report a comprehensive investigation on the epitaxial growth of Sb nanofilms on highly oriented pyrolytic graphite (HOPG) substrate and the controllable thermal desorption to achieve their specific thickness.The morphology,thickness,atomic structure,and thermal-strain effect of the Sb nanofilms were characterized by a combination study of scanning electron microscopy (SEM),atomic force microscopy (AFM),and scanning tunneling microscopy (STM).The realization of Sb nanofilms with specific thickness paves the way for the further exploring their thickness-dependent topological phase transitions and exotic physical properties.