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

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 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 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 way of investigating the behavior of superconducting weak links. This raises the perspective of locally imaging the supercurrent flow, once the spatial resolution is significantly improved, e.g. by nano-sculpting the tip. (Figure presented.)