论文标题
平面约瑟夫森连接处的本地和非局部运输光谱
Local and Nonlocal Transport Spectroscopy in Planar Josephson Junctions
论文作者
论文摘要
我们报告基于外延INAS/Al Hybrid二维异质结构，同时获得了相位偏置的Josephson结的局部和非局部运输光谱。连接端处的量子点接触允许测量局部和非局部隧穿电导的2 x 2矩阵，这是沿连接场的磁场的函数，跨连接的相位差和载体密度。在局部和非局部隧道光谱中观察到了间隙的闭合和重新打开，这是磁场的函数。对于特定的连接密度调节，间隙重新开放伴随着局部电导中的零偏置电导峰（ZBCP）。差距重新打开的端到端相关性很强，而局部ZBCP的相关性较弱。该设备的简单无序模型显示出与拓扑相变相关的可比电导矩阵行为。相位依赖性有助于区分ZBCP的可能起源。
We report simultaneously acquired local and nonlocal transport spectroscopy in a phase-biased planar Josephson junction based on an epitaxial InAs/Al hybrid two-dimensional heterostructure. Quantum point contacts at the junction ends allow measurement of the 2 x 2 matrix of local and nonlocal tunneling conductances as a function of magnetic field along the junction, phase difference across the junction, and carrier density. A closing and reopening of a gap was observed in both the local and nonlocal tunneling spectra as a function of magnetic field. For particular tunings of junction density, gap reopenings were accompanied by zero-bias conductance peaks (ZBCPs) in local conductances. End-to-end correlation of gap reopening was strong, while correlation of local ZBCPs was weak. A simple, disorder-free model of the device shows comparable conductance matrix behavior associated with a topological phase transition. Phase dependence helps distinguish possible origins of the ZBCPs.
