Spin-orbit interaction in HgTe based wires

该项目重点研究由应变HgTe制成的介观纳米线中的干涉现象，该纳米线是一种强三维拓扑绝缘体（TI）。一方面，根据最近的理论建议，我们努力获得表面态拓扑性质的额外证明，另一方面，我们计划系统地研究TI纳米线和环中的量子力学干涉现象。除了电荷载流子的拓扑性质外，这些系统也很有趣，因为导电表面状态围绕着TI的绝缘体，为介观学提供了新的圆柱形几何形状，这在其他材料中很难实现。将要讨论的主题是(i)导线和环中的Aharonov-Bohm振荡和探测相位相干长度，（ii）在导线的磁量子振荡中寻找Dirac表面态的特征，以及（iii）对后门控样品的研究。后一种技术对于我们在单独的工作包中探讨的基于bi的系统也很重要。

The project focuses on interference phenomena in mesoscopic nanowires made from strained HgTe, being a strong 3D topological insulator (TI). On one hand we strive to get additional proof of the topological nature of the surface states following a recent theoretical proposal and, on the other hand, we plan to investigate systematically quantum mechanical interference phenomena in TI nanowires and rings. Apart from the topological nature of the charge carriers these systems are also insofar interesting as the conducting surface states, surrounding the insulating bulk of a TI, enable new cylindrical geometries for mesoscopics, hardly realizable with other materials. Topics to be addressed are (i) Aharonov-Bohm oscillations and probing phase coherence lengths in wires and rings, (ii) the search for signatures of Dirac surface states in magneto-quantum oscillations of wires and (iii) the investigation of back gated samples. The latter technique is also important for Bi-based systems which we explore in a separate work package.