A superconducting resonant tunneling transistor with insulating base layer

A superconducting transistor that uses resonant tunneling as the carrier transport mechanism is proposed. Carriers travel between two superconducting electrodes by resonant tunneling via impurity levels in a barrier. The barrier is a high-dielectric-constant insulator layer sandwiched between low-dielectric-constant layers. The high-dielectric-constant layer conducts an electric field, and the electric potential in the barrier is controlled by voltage applied to the base electrode connected to the edge of the high-dielectric-constant layer. The coupling coefficient between the base and levels may be more than 90% on the average when the emitter stripe width is about 0.1 mu m and the relative dielectric constant of the high-dielectric-constant layer is on the order of 10/sup 4/. The current-versus-voltage characteristics of the transistor were calculated using a tunnel Hamiltonian approximation. The transistor's calculated transconductance was 6*10/sup 6/ S/cm/sup 2/ at a current density of 3*10/sup 4/ A/cm/sup 2/ when the lifetime broadening of resonant levels was 4 meV and the level density was 10/sup 11/ cm/sup -2/.