Granted Patent B2

US 12,414,482 · App. 18/431,342 · Granted Sep 9, 2025

Inventors: Jared B. Hertzberg (Ossining, NY); Jason S. Orcutt (Katonah, NY); Hanhee Paik (Danbury, CT); Sami Rosenblatt (White Plains, NY); Martin O. Sandberg (Ossining, NY)

Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION

H10N60/0884G06N10/40H10N60/0661H10N60/0912H10N60/12H10N60/805

Abstract

Claims (32)

1. A method of forming a multi-qubit chip, the method comprising:

forming a plurality of qubits on a chip, wherein each qubit comprises a Josephson junction and a capacitor connected in parallel with one another;

determining a respective resonance frequency of each qubit on the chip;

determining a respective set-point frequency for each qubit that achieves a defined collision probability with respect to a probability of frequency collisions between adjacent qubits; and

annealing the Josephson junction of a qubit of the plurality of qubits using a laser, based on data that relates parameters for the annealing to frequency shifts, to change the respective resonance frequency of the qubit to about the respective set-point frequency determined for the qubit.

2. The method of claim 1 , wherein the determining the respective resonance frequency for the qubit comprises measuring the respective resonance frequency for the qubit.

3. The method of claim 1 , wherein the determining the respective resonance frequency for the qubit comprises determining the respective resonance frequency for the qubit based upon a measured resistance of the qubit.

4. The method of claim 1 , wherein annealing the Josephson junction comprises localized laser annealing of the Josephson junction.

5. The method of claim 1 , wherein annealing the Josephson junction causes the respective resonance frequency of the qubit to increase.

6. The method of claim 1 , wherein annealing the Josephson junction causes the respective resonance frequency of the qubit to decrease.

7. The method of claim 1 , wherein a parameter of the parameters for annealing the Josephson junction is selected based on the data relating the parameters to the frequency shifts.

8. A method of forming a multi-qubit chip, the method comprising:

determining a respective set-point frequency for each qubit of a plurality of qubits on the multi-qubit chip that achieves a defined collision probability with respect to a probability of frequency collisions between adjacent qubits;

forming the plurality of qubits on the multi-qubit chip in accordance with the respective set-point frequency for each qubit, wherein each qubit comprises a Josephson junction and a capacitor connected in parallel with one another;

determining a frequency of a qubit of the plurality of qubits; and

annealing the Josephson junction of the qubit, based on data defining pre-determining relationships between parameters for the annealing and frequency shifts, to alter the frequency of the qubit to about the respective set-point frequency determined for the qubit.

9. The method of claim 8 , wherein the determining the frequency for the qubit comprises measuring the frequency for the qubit.

10. The method of claim 8 , wherein the determining the frequency for the qubit comprises determining the frequency for the qubit based upon a measured resistance of the qubit.

11. The method of claim 8 , wherein annealing the Josephson junction comprises localized laser annealing of the Josephson junction.

12. The method of claim 8 , wherein annealing the Josephson junction causes the frequency of the qubit to decrease.

13. The method of claim 8 , wherein annealing the Josephson junction causes the frequency of the qubit to increase.

14. The method of claim 8 , wherein forming the plurality of qubits is based on the respective set-point frequency for each of the plurality of qubits, and wherein a first size and a first shape of the qubit are different from a second size and a second shape of another qubit of the plurality of qubits.

15. A method of forming a multi-qubit chip, the method comprising:

forming a plurality of qubits on a chip, wherein each qubit comprises a trilayer Josephson junction and a capacitor connected in parallel with one another, wherein the trilayer Josephson junction comprises a first aluminum layer, an aluminum-oxide layer, and a second aluminum layer;

determining a respective resonance frequency of each qubit on the chip;

determining a respective set-point frequency for each qubit that achieves a defined collision probability with respect to a probability of frequency collisions between adjacent qubit; and

annealing the trilayer Josephson junction of each of the plurality of qubits using a laser, based on a data structure defining pre-determining relationships between parameters for the annealing and frequency shifts, to cause the respective resonance frequency of each of the plurality of qubits to change to the respective set-point frequency determined for each qubit.

16. The method of claim 15 , wherein the determining the respective resonance frequency for a qubit comprises measuring the respective resonance frequency for the qubit.

17. The method of claim 15 , wherein the determining the respective resonance frequency for a qubit comprises determining the respective resonance frequency for the qubit based upon a measured resistance of the qubit.

18. The method of claim 15 , wherein the annealing of the trilayer Josephson junction of a qubit of the plurality of qubits causes the respective resonance frequency of the qubit to increase.

19. The method of claim 15 , wherein the annealing of the trilayer Josephson junction of a qubit of the plurality of qubits causes the respective resonance frequency of the qubit to decrease.

20. The method of claim 15 , wherein the annealing of the trilayer Josephson junction of a qubit of the plurality of qubits comprises localized laser annealing of the trilayer Josephson junction.

Assignments (1)

Continuity (2)

References Cited (171)