Anh Le Duc, Ishihara Keita, Hotta Tomoki, Inagaki Kohdai, Maki Hideki, Saeki Takahiro, Kobayashi Masaki, Tanaka Masaaki
Department of Electrical Engineering and Information Systems, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama, Japan.
Nat Commun. 2024 Sep 30;15(1):8014. doi: 10.1038/s41467-024-52080-4.
High-quality superconductor/topological material heterostructures are highly desired for realisation of topological superconductivity and Majorana physics. Here, we demonstrate a method to directly draw nanoscale superconducting β-Sn patterns in the plane of a topological Dirac semimetal (TDS) α-Sn thin film by irradiating a focused ion beam and taking advantage of the heat-driven phase transition of α-Sn into superconducting β-Sn. The β-Sn nanowires embedded in a TDS α-Sn thin film exhibit a large superconducting diode effect (SDE), whose rectification ratio η reaches a maximum of 35% when the magnetic field is applied parallel to the current. The results suggest that the SDE may occur at the α-Sn/β-Sn interfaces where the TDS α-Sn becomes superconducting by a proximity effect. Our work thus provides a universal platform for investigating quantum physics and devices based on topological superconducting circuits of any shape.
高质量的超导体/拓扑材料异质结构对于实现拓扑超导和马约拉纳物理极为重要。在此，我们展示了一种方法，通过聚焦离子束辐照并利用α-Sn的热驱动相变转变为超导β-Sn，在拓扑狄拉克半金属（TDS）α-Sn薄膜平面内直接绘制纳米级超导β-Sn图案。嵌入TDS α-Sn薄膜中的β-Sn纳米线表现出大的超导二极管效应（SDE），当磁场平行于电流施加时，其整流比η最高可达35%。结果表明，SDE可能发生在TDS α-Sn通过邻近效应变为超导的α-Sn/β-Sn界面处。因此，我们的工作为研究基于任何形状的拓扑超导电路的量子物理和器件提供了一个通用平台。
