论文标题
磁通周期性振荡和基于Gete Nanowire的设备中的相位交通运输
Flux periodic oscillations and phase-coherent transport in GeTe nanowire-based devices
论文作者
论文摘要
尽管众所周知，Gete是一种非常有趣的材料，用于在热电学和相变的记忆中应用，但其低温传输性能的知识仅受到限制。在这里，我们报告了Gete纳米线的磁转运中的相结合现象。从通用电导的波动中，确定孔载体在0.5K时约200 nm的相位共求长度。通过观察到沿纳米线轴施加的磁场的Aharonov-BOHM型振荡，可以证实不同的相位互相关。我们通过在纳米线表面形成管状孔积累层来解释这些磁通周期振荡的发生。此外，对于NB/Gete-Nanowire/NB Josephson连接，我们获得了一个近距离诱导的临界电流，约为0.2 $μ$ a，为0.4K。通过施加垂直于纳米线轴的磁场，临界电流随着磁场的增加而单调降低，这表明结构位于小型单点限制中。鉴于，通过应用平行磁场，临界电流用磁通量量子的周期再次振荡，以再次表明存在管状孔通道。
Despite the fact that GeTe is known to be a very interesting material for applications in thermoelectrics and for phase-change memories, the knowledge on its low-temperature transport properties is only limited. Here, we report on phase-coherent phenomena in the magnetotransport of GeTe nanowires. From universal conductance fluctuations, a phase-coherence length of about 200nm at 0.5K is determined for the hole carriers. The distinct phase-coherence is confirmed by the observation of Aharonov--Bohm type oscillations for magnetic fields applied along the nanowire axis. We interpret the occurrence of these magnetic flux-periodic oscillations by the formation of a tubular hole accumulation layer on the nanowire surface. In addition, for Nb/GeTe-nanowire/Nb Josephson junctions, we obtained a proximity-induced critical current of about 0.2$μ$A at 0.4K. By applying a magnetic field perpendicular to the nanowire axis, the critical current decreases monotonously with increasing magnetic field, which indicates that the structure is in the small-junction-limit. Whereas, by applying a parallel magnetic field the critical current oscillates with a period of the magnetic flux quantum indicating once again the presence of a tubular hole channel.
