Goswami Aranya, Mudi Sanchayeta R, Dempsey Connor, Zhang Po, Wu Hao, Zhang Bomin, Mitchell William J, Lee Joon Sue, Frolov Sergey M, Palmstrøm Christopher J
Electrical and Computer Engineering Department, University of California, Santa Barbara, Santa Barbara, California 93106, United States.
Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States.
Nano Lett. 2023 Aug 23;23(16):7311-7318. doi: 10.1021/acs.nanolett.3c01320. Epub 2023 Aug 10.
Superconductor-semiconductor nanowire hybrid structures are useful in fabricating devices for quantum information processing. While selective area growth (SAG) offers the flexibility to grow semiconductor nanowires in arbitrary geometries, in situ evaporation of superconductors ensures pristine superconductor-semiconductor interfaces, resulting in strong induced superconductivity in the semiconducting nanowire. In this work, we used high-aspect-ratio SiO dielectric walls to in situ evaporate islands of superconductor tin on in-plane InAs SAG nanowires. Our technique enables customization in the designs of such hybrid nanostructures, while simultaneously performing the nanowire and superconductor growth without breaking vacuum. Using this technique, we grew super(S)-normal(N)-super(S), NS, and SNSNS junctions. We performed cryogenic electron transport measurements revealing the presence of gate and field tunable supercurrents. We further measured the superconducting gap and critical fields in the hybrid nanostructures and the crossover from 2e to 1e periodicity in the SNSNS junctions as a proof of the usability of these hybrid nanostructures.
超导-半导体纳米线混合结构在制造用于量子信息处理的器件方面很有用。虽然选择性区域生长（SAG）提供了以任意几何形状生长半导体纳米线的灵活性，但超导体的原位蒸发确保了原始的超导-半导体界面，从而在半导体纳米线中产生强感应超导性。在这项工作中，我们使用高纵横比的SiO介电壁在平面内InAs SAG纳米线上原位蒸发超导锡岛。我们的技术能够定制此类混合纳米结构的设计，同时在不破坏真空的情况下进行纳米线和超导体的生长。使用该技术，我们生长了超（S）-正常（N）-超（S）、NS和SNSNS结。我们进行了低温电子输运测量，揭示了栅极和场可调超导电流的存在。我们进一步测量了混合纳米结构中的超导能隙和临界场，以及SNSNS结中从2e到1e周期性的转变，以证明这些混合纳米结构的可用性。
