摘要
High quality thin films of topological insulators （TI） such as Bi2Se3 have been successfully synthesized by molecular beam epitaxy （MBE）. Although the surface of MBE films can be protected by capping with inert materials such as amorphous Se, restoring an atomically clean pristine surface after decapping has never been demonstrated, which prevents in-depth investigations of the intrinsic properties of TI thin films with ex situ tools. Using high resolution scanning tunneling microscopy/spectroscopy （STM/STS）, we demonstrate a simple and highly reproducible Se decapping method that allows recovery of the pristine surface of extremely high quality Bi2Se3 thin films grown and capped with Se in a separate MBE system then exposed to the atmosphere during transfer into the STM system. The crucial step of our decapping process is the removal of the surface contaminants on top of amorphous Se before thermal desorption of Se at a mild temperature （-210 ~C）. This effective Se decapping process opens up the possibility of ex situ characterizations of pristine surfaces of interesting selenide materials and beyond using cutting-edge techniques.
象双性人那样的拓扑的绝缘体 TI 的高质量的薄电影 < 潜水艇 class= “ a-plus-plus ” > 2 </sub > Se < 潜水艇 class= “ a-plus-plus ” > 3 </sub> 被分子的横梁取向附生 MBE 成功地综合了。尽管 MBE 电影的表面能被与象非结晶的 Se 那样的惰性的材料盖住保护，在 decapping 以后恢复原子地干净的太古的表面从来没被表明过，它与前 situ 工具阻止 TI 薄电影的内在的性质的深入的调查。用扫描通道显微镜学/光谱学 STM/STS 的高分辨率，我们表明允许极其高质量的双性人的太古的表面的恢复的一个简单、高度可再现的 Se decapping 方法<潜水艇class=“ a-plus-plus ”> 2 </sub > Se <潜水艇class=“ a-plus-plus ”>与在一个分开的 MBE 系统的 Se 成年、盖住的薄电影然后暴露了的 3 </sub>到空气在进 STM 系统的转移期间。我们的 decapping 过程的关键步骤是在在温和温度的 Se 的非结晶的 Se 以前热的解吸附作用上的表面沾染物的移动为 A 的 210 石楠<潜水艇class=“ a-plus-plus ”> 1g </sub>模式比那为 E <潜水艇class=“ a-plus-plus ”> 2g </sub><啜class=“ a-plus-plus ”> 1 个</sup>模式。而且，由声子 m 瑐 ? 瑐的移动的使用？？
