Superconducting AC switch system

Patent metadata

Field	Value
Publication number	US-11722135-B2
Application number	US-202117375210-A
Country	US
Kind code	B2
Filing date	Jul 14, 2021
Priority date	Jul 14, 2021
Publication date	Aug 8, 2023
Grant date	Aug 8, 2023

Abstract

A superconducting AC switch system includes a switch network configuration comprising a Josephson junction (JJ) coupled to a transmission line having a transmission line impedance, and a magnetic field generator that is configured to switch from inducing a magnetic field in a plane of the JJ, and providing no magnetic field in the plane of the JJ. An AC input signal applied at an input of the switch network configuration is passed through to an output of the switch network configuration in a first magnetic state, and substantially reflected back to the input of the switch network configuration in a second magnetic state. The first magnetic state is one of inducing and not inducing a magnetic field in a plane of the JJ, and the second magnetic state is the other of inducing and not inducing a magnetic field in a plane of the JJ.

First claim

What is claimed is:

1. A superconducting AC switch system comprising:
a parellel switch network comprising a Josephson junction (JJ) coupled at a first end to an intermediate point in a transmission line having a transmission line impedance and at a second end to ground; and
a magnetic field generator that is configured to switch from inducing a magnetic field in a plane of the JJ, and providing no magnetic field in the plane of the JJ,
wherein an AC input signal applied at an input of the parallel switch network is passed through to an output of the parallel switch network in a first magnetic state, and the AC input signal applied at the input of the parallel switch network is substantially reflected back to the input of the parallel switch network in a second magnetic state,
wherein the first magnetic state is one of inducing a magnetic field in a plane of the JJ, and providing no magnetic field in the plane of the JJ, and the second magnetic state is the other of inducing a magnetic field in a plane of the JJ, and providing no magnetic field in the plane of the JJ.

2. The system of claim 1 , wherein inducing a magnetic field in a plane of the JJ causes the JJ to have an impedance larger than the transmission line impedance and providing no magnetic field in the plane of the JJ allows the JJ to superconduct and have an impedance smaller than the transmission line impedance.

3. The system of claim 1 , wherein the transmission line has a first transmission line portion coupled to the input of the parallel switch network and a second transmission line portion coupled to an output of the parallel switch network, wherein the JJ is disposed between the first transmission line portion at an end opposite the input and the second transmission line portion at an end opposite the output.

4. The system of claim 3 , wherein the JJ superconducts and shorts the intermediate point to ground when no magnetic field is provided in the plane of the JJ and provides an impedance larger than the transmission line impedance when a magnetic field is induced in the plane of the JJ.

5. The system of claim 4 , wherein the parallel switch network comprises a plurality of parallel switch network circuits each having a respective JJ coupled at a first end to an intermediate point in a respective transmission line and to ground on a second end, wherein each respective JJ superconducts and shorts the intermediate point to ground when no magnetic field is provided in the plane of the JJ and provides an impedance larger than the transmission line impedance when a magnetic field is induced in the plane of the JJ, wherein the magnetic field generator is configured to induce a magnetic field in a JJ of a selected one of the plurality of parallel switch network circuits and not the JJs in the non-selected ones of the plurality of switch network circuits, such that an AC signal provided at inputs of one or more of the plurality of parallel switch network circuits is provided at the output of the selected one of the plurality of parallel switch network circuits.

6. The system of claim 5 , wherein the inputs of each of the plurality of parallel switch network circuits are connected to a same port and each output of the plurality of parallel switch network circuits are coupled to respective dedicated output ports.

7. The system of claim 5 , wherein the inputs of each of the plurality of parallel switch network circuits are connected to respective dedicated ports and each output of the plurality of parallel switch network circuits are coupled to a same output port.

8. The system of claim 3 , wherein the switch network configuration comprises a series switch network circuit, wherein the JJ has a first end connected to the first transmission line portion at an end opposite the input and the JJ has a second end connected to the second transmission line portion at an end opposite the output.

9. The system of claim 8 , wherein the switch network configuration comprises a plurality of series switch network circuits each having a respective JJ coupled at a first end to a respective first transmission line portion of a respective transmission line and to a respective second transmission line portion of the respective transmission line, wherein the magnetic field generator is configured to induce magnetic fields in the JJs of each of the plurality of switch network circuits but a selected one of the plurality of switch network circuits such that a AC signal provided at inputs of one or more of the plurality of series switch network circuits is provided at the output of the selected one of the plurality of series switch network circuits.

10. The system of claim 9 , wherein the inputs of each of the plurality of switch network circuits are connected to a same port and each output of the plurality of switch network circuits are coupled to respective dedicated output ports.

11. The system of claim 9 , wherein the inputs of each of the plurality of switch network circuits are connected to respective dedicated ports and each output of the plurality of switch network circuits are coupled to a same output port.

12. The system of claim 1 , wherein the induced magnetic field is selected to suppress the critical current of the JJ to substantially zero.

13. The system of claim 1 , further comprising one or more additional impedance components configured in parallel with the JJ to provide a filter circuit that provides a filtered output response.

14. The system of claim 1 , wherein the magnetic field generator is a solenoid with a loop winding that surrounds the one or more JJs.

15. The system of claim 1 , wherein the magnetic field generator is a bias line in close enough proximity to the one or more JJs that when current-biased generates a sufficiently strong magnetic field in a plane of the one or more JJs so as to suppress the critical current substantially to zero.

16. A superconducting AC switch system comprising:
a parallel switch network comprising a plurality of parallel switch network circuits each having a respective Josephson junction (JJ) coupled at a first end to an intermediate point in a respective transmission line having a respective transmission line impedance, and a ground on a second end; and
a switch controller configured to control the selective switching of the inducing of a magnetic field in a plane of a respective JJ and the providing of no magnetic field in a plane of a respective JJ for each respective JJ of the plurality of parallel switch network circuits, wherein induction of a magnetic field in a plane of a respective JJ provides the JJ with an impedance larger than the transmission line impedance of its respective transmission line and the providing of no magnetic field in a plane of a respective JJ allows the JJ to superconduct and have an impedance smaller than the transmission line impedance of its respective transmission line, the switch controller configured to select a selected one or more of the plurality of parallel switch networks to pass a received AC input signal to the output of the selected parallel switch network circuit, while blocking the passing of a received AC input signal through non-selected parallel switch network circuits of the plurality of parallel switch network circuits.

17. The system of claim 16 , wherein the respective JJ superconducts and shorts the intermediate point to ground when no magnetic field is provided in the plane of the respective JJ and provides an impedance larger than the transmission line impedance of its respective transmission line when a magnetic field is induced in the pla

Assignees

• Graninger Aurelius L
• Pesetski Aaron A
• Strand Joel D
• Northrop Grumman Systems Corp

Inventors

• Graninger Aurelius L
• Pesetski Aaron A
• Strand Joel D

Classifications

• H03K17/92 Primary

  by the use, as active elements, of superconductive devices · CPC title

• H01F7/064

  Circuit arrangements for actuating electromagnets (circuit arrangements for obtaining special operating characteristics H01F7/18; driving circuits for electromagnets making use of a switching regulator H01H47/325) · CPC title

• H03K17/002

  Switching arrangements with several input- or output terminals (code converters H03M5/00, H03M7/00) · CPC title