论文标题
自定义的介于介质INAS/al nanowire Josephson结中的硬隙光谱法
Hard-gap spectroscopy in a self-defined mesoscopic InAs/Al nanowire Josephson junction
论文作者
论文摘要
超导体/半导体 - 纳米线混合结构可以用作多功能的构建块，以实现基于量化水平（例如Andreev Qubits）的Majorana电路或超导码头。对于所有这些应用，至关重要的是，超导体 - 触发器界面尽可能干净。此外，需要精确控制超导电极的形状和尺寸。我们通过完全符合所有这些标准的方法制造了自定义的INAS/al core/shell纳米线连接。透射电子显微镜测量结果证实了纳米线与原位沉积的Al电极之间的尖锐而干净的界面，这些界面是通过阴影蒸发形成的。此外，我们报告了隧道光谱，栅极和磁场依赖性传输测量值。可实现的短连接长度，观察到的硬间隙和磁场鲁棒性使这种新的混合结构对于依赖于对亚漏的状态数量的精确控制的应用非常有吸引力，例如Andreev Qubits或拓扑系统。
Superconductor/semiconductor-nanowire hybrid structures can serve as versatile building blocks to realize Majorana circuits or superconducting qubits based on quantized levels such as Andreev qubits. For all these applications it is essential that the superconductor-semiconductor interface is as clean as possible. Furthermore, the shape and dimensions of the superconducting electrodes needs to be precisely controlled. We fabricated self-defined InAs/Al core/shell nanowire junctions by a fully in-situ approach, which meet all these criteria. Transmission electron microscopy measurements confirm the sharp and clean interface between the nanowire and the in-situ deposited Al electrodes which were formed by means of shadow evaporation. Furthermore, we report on tunnel spectroscopy, gate and magnetic field-dependent transport measurements. The achievable short junction lengths,the observed hard-gap and the magnetic field robustness make this new hybrid structure very attractive for applications which rely on a precise control of the number of sub-gap states, like Andreev qubits or topological systems.
