Superconducting single-pole double-throw switch system

Patent metadata

Field	Value
Publication number	US-9768771-B2
Application number	US-201514616451-A
Country	US
Kind code	B2
Filing date	Feb 6, 2015
Priority date	Feb 6, 2015
Publication date	Sep 19, 2017
Grant date	Sep 19, 2017

Abstract

A superconducting switch system is provided that includes a filter network having a first SQUID coupled to a second SQUID via a common node, an input port coupled to the common node, a first output port coupled to the first SQUID, and a second output port coupled to the second SQUID. The superconducting switch system also includes a switch controller configured to control an amount of induced current through the first SQUID and the second SQUID to alternately switch the first and second SQUIDS between first inductance states in which a desired bandwidth portion of a signal provided at the input terminal passes to the first output terminal and is blocked from passing to the second output terminal, and second inductance states in which the desired bandwidth portion of the input signal passes to the second output terminal and is blocked from passing to the first output terminal.

First claim

What is claimed is:

1. A superconducting switch system comprising:
a first Superconducting Quantum Interference Device (SQUID) having a first variable inductance coupling element;
a second SQUID having a second variable inductance coupling element, the second SQUID being coupled to the first SQUID through a common node;
a first terminal coupled to the common node;
a second terminal coupled to the first SQUID through an end opposite the common node;
a third terminal coupled to the second SQUID through an end opposite the common node;
a common mode flux bias line inductively coupled to the first and second SQUIDs and to induce a common mode flux in each of the first SQUID and second SQUID based on a first biasing current flowing through the common mode flux bias line;
a differential mode flux bias line to induce a first differential mode flux in the first SQUID and a second differential mode flux in the second SQUID based on a second biasing current flowing through the differential mode flux bias line; and
a switch controller configured to control the setting of the first variable inductance coupling element and the second variable inductance coupling element between opposing inductance states based on both the first and the second biasing currents to allow selective routing of signals between one of a first path between the first terminal and the second terminal and a second path between the first terminal and the third terminal,
wherein the first, second, and third terminals are not on either of the common mode flux bias line or the differential mode flux bias line.

2. The system of claim 1 , wherein the first and second variable inductance coupling elements are flux-controlled variable inductors that provide the variable inductance based on an amplitude of a current flowing through the flux-controlled variable inductor.

3. The system of claim 2 , wherein the variable inductance coupling element comprises a Josephson junction.

4. The system of claim 1 , wherein the first SQUID is formed of a first inductor, the first variable inductance element which is a first Josephson junction and a second inductor, and the second SQUID is formed of the second inductor, the second variable inductance element which is a second Josephson junction, and a third inductor.

5. The system of claim 4 , wherein the common mode flux bias line comprises a common bias inductor inductively coupled to the second inductor, and the differential mode flux bias line comprises a first differential bias inductor inductively coupled to the first inductor, and a second differential bias inductor inductively coupled to the third inductor.

6. The system of claim 1 , wherein the switch controller controls an amount of the first biasing current through the common mode flux bias line and an amount of the second biasing current through the differential mode flux bias line and the polarity of current through one of the common mode flux bias line and the differential mode flux bias line, wherein the changing of polarity of current changes the selection between routing of signals through one of the first path and the second path.

7. The system of claim 6 , wherein the switch controller provides the first and the second biasing currents and polarity of the first and the second biasing currents to the common mode flux bias line and the differential mode flux line when selecting a path that results in one of the first SQUID and second SQUID having a net flux of approximately zero and the other of the first SQUID and second SQUID having a net flux of about 0.1Φ 0 to about 0.45 Φ 0 , where Φ 0 is equal to a flux quantum.

8. The system of claim 1 , further comprising a first coupling capacitor coupled between the first terminal and the common node, a second coupling capacitor coupled between the second terminal and the first SQUID and a third coupling capacitor coupled between the third terminal and the second SQUID, wherein the first, second and third coupling capacitors assure that currents that flow through the first and second SQUIDs are isolated from flowing though other parts of the system.

9. A superconducting switch comprising:
a first Superconducting Quantum Interference Device (SQUID) having a first inductor, a first Josephson junction and a common inductor arranged in a first superconducting loop;
a second SQUID having the common inductor, a second Josephson junction and a second inductor arranged in a second superconducting loop;
a first terminal coupled to a common node, the common node being connected to a first end of the common inductor, a first end of the first Josephson junction and a first end of the second Josephson junction;
a second terminal coupled to a second end of the first Josephson junction and a first end of the first inductor;
a third terminal coupled to a second end of the second Josephson junction and a first end of the second inductor;
a common mode flux bias line comprising a common bias inductor inductively coupled to common inductor; and
a differential mode flux bias line comprising a first differential bias inductor inductively coupled to the first inductor, and a second differential bias inductor inductively coupled to the second inductor,
wherein the first, second, and third terminals are not on either of the common mode flux bias line or the differential mode flux bias line.

10. The switch of claim 9 , wherein an amount of current applied through the common mode flux bias line and the differential mode flux bias line and the polarity of current through one of the common mode flux bias line and the differential mode flux bias line provides a net flux of approximately zero in one of the first and second SQUIDs, and a flux of a substantial fraction of a ½ of flux quantum in the other of the first and second SQUIDs, which results in the selective routing of signals through one of the first terminal and the second terminal, and the first terminal and the third terminal.

11. The system of claim 9 , further comprising a first coupling capacitor coupled between the first terminal and the common node, a second coupling capacitor coupled between the second terminal and the first SQUID and a third coupling capacitor coupled between the third terminal and the second SQUID, wherein the first, second and third coupling capacitors assure that currents that flow through the first and second SQUIDs are isolated from flowing though other parts of the system.

Assignees

• Naaman Ofer
• Northrop Grumman Systems Corp

Inventors

• Naaman Ofer

Classifications

• H03K17/92 Primary

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