Control of supercurrent in a self-assembled InAs quantum dot Josephson junction by electrical tuning of level overlaps

Abstract

We study supercurrent in a single InAs self-assembled quantum dot contacted with superconducting leads and demonstrate that for regions where energy level spacing and charging energy are smaller than tunnel coupling, the supercurrent may be controlled by the degree of overlaps between energy levels, which is tunable using a side-gate electrode. In such regions, we find strong correlation between the supercurrent and the normal state conductance when the device parameters are tuned. In a Kondo regime with low Kondo temperature, we find that the scaling of the supercurrent and normal state conductance varies when the side-gate voltage is changed.