Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, People's Republic of China. School of Materials Science and Engineering, University of Science and Technology of China, Hefei 230026, People's Republic of China.
Nanotechnology. 2019 Jul 5;30(27):275703. doi: 10.1088/1361-6528/ab13cf. Epub 2019 Mar 27.
We report the magneotransport studies on the topological crystalline insulator (TCI) Pb Sn Te (111) single crystal thin films grown by molecular beam epitaxy. By decreasing Sn content, an enhanced sheet resistance and decreased hole density are observed in Pb Sn Te (111) thin films. A weak antilocalization likely related to the topological surface states is observed in transport of Pb Sn Te (x > 0.4) thin films, whereas a weak localization is displayed in Pb Sn Te (x < 0.4) thin films. This tunable weak antilocalization to weak localization transition is attributed to the open of Dirac gap because of the topological phase transition in TCI Pb Sn Te. Our research has a potential application in the tunable electronic and spintronic devices and is very significant to the fundamental research based on TCI Pb Sn Te thin film.
我们报道了通过分子束外延生长的拓扑晶体绝缘体（TCI）PbSnTe（111）单晶薄膜的磁输运研究。通过降低 Sn 含量，PbSnTe（111）薄膜的薄层电阻增大，空穴密度减小。在 PbSnTe（x>0.4）薄膜的输运中观察到与拓扑表面态相关的弱反局域，而在 PbSnTe（x<0.4）薄膜中则显示出弱局域。这种可调谐的弱反局域到弱局域转变归因于拓扑相变导致 TCI PbSnTe 的狄拉克能隙的打开。我们的研究在可调谐电子和自旋电子器件中有潜在的应用，对基于 TCI PbSnTe 薄膜的基础研究具有重要意义。
