Qubit tuning by magnetic fields in superconductors

Patent metadata

Field	Value
Publication number	US-11501196-B2
Application number	US-201816200062-A
Country	US
Kind code	B2
Filing date	Nov 26, 2018
Priority date	Nov 26, 2018
Publication date	Nov 15, 2022
Grant date	Nov 15, 2022

Abstract

An embodiment of a qubit tuning device includes a first layer configured to generate a magnetic field, the first layer comprising a material exhibiting superconductivity in a cryogenic temperature range. In an embodiment, the qubit tuning device includes a qubit of a quantum processor chip, wherein the first layer is configured to magnetically interact with the qubit such that a first magnetic flux of the first layer causes a first change in a first resonance frequency of the qubit by a first frequency shift value.

First claim

What is claimed is:

1. A device comprising:
a first layer configured to generate a magnetic field, the first layer comprising a material exhibiting superconductivity in a cryogenic temperature range;
a qubit of a quantum processor chip, wherein the first layer is configured to magnetically interact with the qubit such that a first magnetic flux of the first layer causes a first change in a first resonance frequency of the qubit by a first frequency shift value; and
a heating element configured to heat a portion of the first layer above a critical temperature.

2. The device of claim 1 , further comprising:
a magnetic element configured to apply a magnetic field to the first layer.

3. The device of claim 2 , wherein the heating element is a resistor.

4. The device of claim 2 , wherein the heating element is a light source.

5. The device of claim 2 , the magnetic element comprising:
a wire of a superconducting material, the wire being formed into a coil structure.

6. The device of claim 2 , wherein the heating element is one of a plurality of heating elements, each heating element configured to heat a corresponding portion of the first layer above a critical temperature.

7. The device of claim 6 , wherein each portion of the first layer is configured to magnetically interact with a corresponding qubit of a plurality of qubits of the quantum processor such that a magnetic flux of each portion causes a change in a resonance frequency of the corresponding qubit.

8. The device of claim 1 , wherein the first layer produces the first magnetic flux while operating in a range of temperatures between 20 Kelvin and 0.01 Kelvin, inclusive of both ends of the range.

9. The device of claim 1 , further comprising:
a second layer configured to generate a magnetic field, the second layer comprising a material exhibiting superconductivity in a cryogenic temperature range.

10. The device of claim 1 , further comprising:
a magnetic element disposed on a surface of a chip, wherein the first layer is formed on an opposite surface of the chip.

11. The device of claim 1 , wherein the qubit is formed on a first surface of the quantum processor chip; and
wherein the first layer is formed on an opposite surface of the quantum processor chip.

12. The device of claim 1 , further comprising:
a magnetic element configured to apply a magnetic field to the first layer, the magnetic element disposed on a first chip; and
wherein the first layer is disposed on a second chip.

13. A method to fabricate a qubit tuning device, the method comprising:
forming a first layer configured to generate a magnetic field, the first layer comprising a material exhibiting superconductivity in a cryogenic temperature range;
forming a qubit on a quantum processor chip, wherein the first layer is configured to magnetically interact with the qubit such that a first magnetic flux of the first layer causes a first change in a first resonance frequency of the qubit by a first frequency shift value; and
heating, using a heating element, a portion of the first layer above a critical temperature.

14. The method of claim 13 , further comprising:
forming a second layer configured to generate a magnetic field, the second layer comprising a material exhibiting superconductivity in a cryogenic temperature range.

15. The method of claim 13 , wherein the first layer produces the first magnetic flux while operating in a range of temperatures between 20 Kelvin and 0.01 Kelvin, inclusive of both ends of the range.

16. The method of claim 13 , further comprising:
disposing a magnetic element on a surface of a chip, wherein the first layer is formed on an opposite surface of the chip.

17. The method of claim 13 , wherein the qubit is formed on a first surface of the quantum processor chip; and
wherein the first layer is formed on an opposite surface of the quantum processor chip.

18. A superconductor fabrication system which when operated to fabricate a qubit tuning device performs operations comprising:
forming a first layer configured to generate a magnetic field, the first layer comprising a material exhibiting superconductivity in a cryogenic temperature range;
forming a qubit on a quantum processor chip, wherein the first layer is configured to magnetically interact with the qubit such that a first magnetic flux of the first layer causes a first change in a first resonance frequency of the qubit by a first frequency shift value; and
heating, using a heating element, a portion of the first layer above a critical temperature.

19. The superconductor fabrication system of claim 18 , the operations further comprising:
forming a second layer configured to generate a magnetic field, the second layer comprising a material exhibiting superconductivity in a cryogenic temperature range.

20. The superconductor fabrication system of claim 18 , the operations further comprising:
disposing a magnetic element on a surface of a chip, wherein the first layer is formed on an opposite surface of the chip.

Assignees

• IBM

Inventors

• Frisch Albert
• Barowski Harry
• Brink Markus

Classifications

• H05K7/20372

  Cryogenic cooling; Nitrogen liquid cooling · CPC title

• H05B3/0033

  Heating devices using lamps · CPC title

• G06F15/7807

  System on chip, i.e. computer system on a single chip; System in package, i.e. computer system on one or more chips in a single package · CPC title

• G06N10/00 Primary

  Quantum computing, i.e. information processing based on quantum-mechanical phenomena · CPC title

• H01F6/06 Primary

  Coils, e.g. winding, insulating, terminating or casing arrangements therefor · CPC title