Behner Gerrit, Jalil Abdur Rehman, Rupp Alina, Lüth Hans, Grützmacher Detlev, Schäpers Thomas
Peter Grünberg Institut (PGI-9), Forschungszentrum Jülich, 52425 Jülich, Germany.
JARA-Fundamentals of Future Information Technology, Jülich-Aachen Research Alliance, Forschungszentrum Jülich and RWTH Aachen University, 52425 Jülich, Germany.
ACS Nano. 2025 Jan 28;19(3):3878-3885. doi: 10.1021/acsnano.4c15893. Epub 2025 Jan 13.
The combination of an ordinary s-type superconductor with three-dimensional topological insulators creates a promising platform for fault-tolerant topological quantum computing circuits based on Majorana braiding. The backbone of the braiding mechanism are three-terminal Josephson junctions. It is crucial to understand the transport in these devices for further use in quantum computing applications. We present low-temperature measurements of topological insulator-based three-terminal Josephson junctions fabricated by a combination of selective-area growth of BiSbTe and shadow mask evaporation of Nb. This approach allows for the in situ fabrication of Josephson junctions with an exceptional interface quality, important for the study of the proximity-effect. We map out the transport properties of the device as a function of bias currents and prove the coupling of the junctions by the observation of a multiterminal geometry-induced diode effect. We find good agreement of our findings with a resistively and capacitively shunted junction network model.
普通s型超导体与三维拓扑绝缘体相结合，为基于马约拉纳编织的容错拓扑量子计算电路创造了一个很有前景的平台。编织机制的核心是三端约瑟夫森结。了解这些器件中的输运情况对于量子计算应用的进一步发展至关重要。我们展示了通过BiSbTe的选择性区域生长和Nb的阴影掩膜蒸发相结合制造的基于拓扑绝缘体的三端约瑟夫森结的低温测量结果。这种方法允许原位制造具有卓越界面质量的约瑟夫森结，这对于研究近邻效应很重要。我们绘制了器件的输运特性随偏置电流的变化关系，并通过观察多端几何结构诱导的二极管效应证明了结的耦合。我们发现我们的结果与电阻和电容并联结网络模型有很好的一致性。
