Quasiballistic quantum transport through Ge/Si core/shell nanowires

We study signatures of ballistic quantum transport of holes through Ge/Si core/shell nanowires at low temperatures. We observe Fabry–Pérot interference patterns as well as conductance plateaus at integer multiples of 2e2/h at zero magnetic field. Magnetic field evolution of these plateaus reveals relatively large effective Landé g-factors. Ballistic effects are observed in nanowires with silicon shell thickness of 1–3 nm, but not in bare germanium wires. These findings inform the future development of spin and topological quantum devices which rely on ballistic sub-band-resolved transport.

我们研究低温下空穴通过锗/硅核/壳纳米线的弹道量子输运特征。我们在零磁场下观察到法布里 - 珀罗干涉图案以及在2e²/h整数倍处的电导平台。这些平台的磁场演化揭示出相对较大的有效朗德g因子。在硅壳厚度为1 - 3纳米的纳米线中观察到弹道效应，但在裸锗线中未观察到。这些发现为依赖于弹道子带分辨输运的自旋和拓扑量子器件的未来发展提供了信息。