The electro-magnetostatic Aharonov–Bohm effect as a tool to tune the Josephson current

The electro-magnetostatic Aharonov–Bohm effect is shown to allow a full control of a Josephson junction. Both the sign and the magnitude of the supercurrent can be tuned if the junction between two superconductors is realized with a ring-shaped ballistic normal region. The implementation in a realistic set-up is discussed.