A three-terminal superconducting devise composed of a semiconductor coupled Josephson junction and an oxide-insulated gate was described. It was possible to control the superconducting coherence length ξn in the semiconductor by applying a gate voltage; consequently, the junction's superconducting critical current, which depends on ξn, was changeable. Power dissipation and switching time constant would be expected to be approximately 1μW and 10ps, respectively.
