Supercurrent modulation in InSb nanoflag-based Josephson junctions by scanning gate microscopy

Antonio Lombardi; Gaurav Shukla; Giada Bucci; Sedighe Salimian; Valentina Zannier; Simone Traverso; Samuele Fracassi; Niccolo Traverso Ziani; Maura Sassetti; Matteo Carrega; Fabio Beltram; Lucia Sorba; Stefan Heun

doi:10.1038/s43246-025-01000-0

arXiv · 2506.15342

Supercurrent modulation in InSb nanoflag-based Josephson junctions by scanning gate microscopy

Antonio Lombardi·Gaurav Shukla·Giada Bucci·Sedighe Salimian·Valentina Zannier·Simone Traverso·Samuele Fracassi·Niccolo Traverso Ziani·Maura Sassetti·Matteo Carrega·Fabio Beltram·Lucia Sorba·Stefan Heun

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Abstract

InSb nanoflags represent an interesting platform for quantum transport and have recently been exploited in the study of hybrid planar Josephson junctions. Due to the uncovered semiconductor surface, they are also good candidates for surface probe techniques. Here, we report the first Scanning Gate Microscopy (SGM) experiments on Nb-contacted InSb nanoflag-based Josephson junctions. In the normal state, sizable conductance modulation via the charged tip of the SGM is recorded. In the superconducting state, we report the first application of Scanning Gate Microscopy to superconducting weak links, demonstrating the possibility of manipulating the supercurrent flow across a semiconductor-superconductor heterostructure at a local level. The experimental findings are consistent with theoretical predictions and establish a new way of investigating the behavior of superconducting weak links, towards the local imaging of supercurrent flow.

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Antonio Lombardi, Gaurav Shukla, Giada Bucci, Sedighe Salimian, Valentina Zannier, Simone Traverso, Samuele Fracassi, Niccolo Traverso Ziani, Maura Sassetti, Matteo Carrega, Fabio Beltram, Lucia Sorba, Stefan Heun. 2025-06-18. Supercurrent modulation in InSb nanoflag-based Josephson junctions by scanning gate microscopy. https://doi.org/10.1038/s43246-025-01000-0

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