Josephson current in nanofabricated V/Cu/V mesoscopic junctions

We report the fabrication of planar V/Cu/V mesoscopic Josephson weak links of different size and the analysis of their low-temperature behavior. The shorter junctions exhibit critical currents of several tens of microamperes at 350 mK, while Josephson coupling persists up to ∼2.7 K. Good agreement is obtained by comparing the measured switching currents to a model which holds in the diffusive regime. Our results demonstrate that V is an excellent candidate for the implementation of superconducting nanodevices operating at a few kelvins.