Controlled Tunneling Through the Superconducting Energy Gap
Original Publication Date: 1985-Apr-01
Included in the Prior Art Database: 2005-Feb-18
An electrically isolated superconducting control electrode, used to modulate the tunneling current between two other metallic electrodes, provides a transistor which achieves millivolt operation by using the novel effect of tunneling through the naturally occurring millivolt energy gap of the superconducting control electrode. The device has a composite tunnel barrier between the source and drain electrodes. The actual tunnel barrier is a composite structure consisting of two thin insulators and a superconductor, the energy gap of which acts as only a part of the tunnel barrier. By applying a voltage to the superconductor, the tunneling current through the entire structure can be varied, and the device can act as a switch.