NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore , I-56127 Pisa, Italy.
Nano Lett. 2015 Mar 11;15(3):1803-8. doi: 10.1021/nl504544s. Epub 2015 Feb 16.
We have studied mesoscopic Josephson junctions formed by highly n-doped InAs nanowires and superconducting Ti/Pb source and drain leads. The current-voltage properties of the system are investigated by varying temperature and external out-of-plane magnetic field. Superconductivity in the Pb electrodes persists up to ∼7 K and with magnetic field values up to 0.4 T. Josephson coupling at zero backgate voltage is observed up to 4.5 K and the critical current is measured to be as high as 615 nA. The supercurrent suppression as a function of the magnetic field reveals a diffraction pattern that is explained by a strong magnetic flux focusing provided by the superconducting electrodes forming the junction.
我们研究了由高度 n 型掺杂 InAs 纳米线和超导 Ti/Pb 源极和漏极形成的介观约瑟夫森结。通过改变温度和外部平面外磁场来研究系统的电流-电压特性。在约 7 K 的温度和高达 0.4 T 的磁场值下，Pb 电极中的超导性仍然存在。在零背栅电压下观察到约瑟夫森耦合，最高可达 4.5 K，测量到的临界电流高达 615 nA。随着磁场的变化，超电流抑制呈现出一种衍射图案，这可以通过形成结的超导电极提供的强磁通聚焦来解释。
