Superconducting switch and amplifier device

A superconducting device, comprising in combination:

• first, second, and third current carrying electrodes, said second and third electrodes being superconductors, there being tunneling barriers located between said first and second electrodes, and between said second and third electrodes, wherein the current-voltage characteristic of the tunnel junction comprising said second and third electrodes and the tunnel barrier therebetween exhibits a sharp current transition in its current-voltage characteristic at n(.DELTA..sub.2 +.DELTA..sub.3), where n=1, 2 and .DELTA..sub.2 and .DELTA..sub.3 are the superconducting bandgaps of said second and third electrodes, respectively,
• injector means for injecting excess energetic quasi-particles into said second electrode to produce sufficient injection that .DELTA..sub.2 .fwdarw.0, said injector means including said first electrode and the tunnel barrier between said first and second electrodes.

A NOR circuit comprising at least three superconducting devices, each of said superconducting devices being comprised of an acceptor tunnel junction including a first superconducting electrode, a tunnel barrier in contact with said first superconducting electrode, a second electrode, and means for injecting excess quasi-particles into said superconducting electrode to drastically change its superconducting bandgap, the second electrodes of said superconducting devices being electrically connected, and bias means for providing a current through said first and second electrodes and the tunnel barrier therebetween.

A superconducting device, comprising in combination:

• a tunnel junction comprising first and second electrodes and a tunnel barrier therebetween where said first electrode is comprised of a superconducting material,
• a plurality of injection means for injecting excess quasi-particles into said first superconducting electrode in order to make the superconducting bandgap of said first electrode vanish.

A superconducting device comprising, in combination:

• a tunnel junction comprising first and second electrodes separated by a tunnel barrier, said first and second electrodes being comprised of superconducting materials having superconducting bandgaps .DELTA..sub.2 and .DELTA..sub.3, respectively, said tunnel junction being characterized by a threshold power density P.sub.c at which the superconducting gap .DELTA..sub.2 vanishes,
• injection means for injecting power into said first superconducting electrode, said injection means producing an injection current density j.sub.i into said first superconducting electrode having a magnitude such that P.sub.c is reached at output voltages from said superconducting device in the order of (.DELTA..sub.2 +.DELTA..sub.3).

A superconducting device comprising, in combination:

• a tunnel junction providing a voltage output V across a load and a including a current-carrying superconductor for carrying current which tunnels through said junction, said superconductor having a superconducting bandgap .DELTA. characterized by a threshold power density P.sub.c at which .DELTA. vanishes,
• injection means for injecting power into said superconductor,
• said injection means producing an injection current density j.sub.i into said superconductor having a magnitude such that P.sub.c is reached at a voltage V in excess of said bandgap .DELTA..

A superconducting device, comprising:

• injection means including a first superconductor with a superconducting bandgap .DELTA..sub.1 for injecting power into a second superconductor having a superconducting bandgap .DELTA..sub.2, said injection means producing excess quasi-particles in said second superconductor of an amount such that a threshold power density P.sub.c at which .DELTA..sub.2 .fwdarw.0 is reached at a voltage in excess of said bandgap .DELTA..sub.2,
• a tunnel device having a tunnel current therethrough and including said second superconductor, said tunnel device having a threshold power density relationship P.sub.c (.epsilon.) which exhibits a sharp transition at .epsilon.=eV.sub.TC /(.DELTA..sub.1 +.DELTA..sub.2).apprxeq.1 such that P.sub.c (0)/P.sub.c (.infin.) is >>1.