IP Library › Granted Patent US 12,271,786
Granted Patent B2
US 12,271,786 · App. 18/053,087 · Granted Apr 8, 2025

Preparation of a CZ state for quantum computation

Inventors: Benjamin James Brown (Copenhagen, DK); Andrew W. Cross (Yorktown Heights, NY); Riddhi Swaroop Gupta (San Jose, CA); Tomas Raphael Jochym-O'Connor (Los Angeles, CA); Theodore James Yoder (Mohegan Lake, NY)
Assignee: International Business Machines Corporation
G06N10/70G06N10/20
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Quick Facts
Patent No.
US 12,271,786
App. No.
18/053,087
Granted
Apr 8, 2025
Kind
B2
Abstract

According to an embodiment of the present invention, a method, system, and computer program product for preparing a CZ state for use in magic state distillation. The embodiment may include initializing a code state across data qubits. The embodiment may include measuring a CZ operator of the codes state on at least one ancilla qubit proximal to the data qubits. The embodiment may include performing additional quantum operations with the CZ state based on the measurement of the at least one ancilla qubit.

Claims (48)

1. A method comprising:

initializing a code state across data qubits, wherein an initial code state is obtained through post selection;

measuring a CZ operator of the codes state on at least one ancilla qubit proximal to the data qubits; and

based on the measurement of the at least one ancilla qubit, performing additional quantum operations with the CZ state.

2. The method of claim 1 , wherein initializing the code state across data qubits comprises: initializing each data qubit in a state;

performing a Pauli-X stabilizer circuit with single qubit rotations onto each data qubit; and

measuring the at least one ancilla qubit.

3. The method of claim 2 further comprising based on the measurement result of the at least one ancilla qubit, performing an additional correction to the data qubits.

4. The method of claim 3 , wherein the additional correction comprises a X-rotation on a single qubit.

5. The method of claim 1 , wherein measuring the CZ operator comprises:

performing a Pauli-X stabilizer circuit with specific single qubit rotations onto data qubits; and

measuring at least one ancilla qubit.

6. The method of claim 1 further comprising:

performing at least one error detecting measurement prior to performing additional operations with the CZ state.

7. The method of claim 6 , wherein the at least one error detecting measurement comprises:

performing a Pauli-X stabilizer circuit with a single qubit rotation onto data qubits; and

measuring at least ancilla qubit.

8. The method of claim 1 further comprising reinitializing the CZ state across data qubits based on a measurement of the ancilla qubit.

9. A system comprising one or more processors, one or more computer readable memories, one or more computer readable storage devices, one or more computer-readable storage devices, one or more classical-quantum interfaces, and one or more quantum hardware and program instructions stored on the one or more computer readable storage devices for execution by one or more processors via the one or more memories to operate the one or more classical-quantum interface to operate the one or more quantum hardware according the program instructions, the program instructions comprising instructions for:

initializing a code state across data qubits;

measuring a CZ operator of the codes state on at least one ancilla qubit proximal to the data qubits; and

based on the measurement of the at least one ancilla qubit, performing additional quantum operations with the CZ state.

10. The system of claim 9 , wherein initializing the code state across data qubits

comprises: initializing each data qubit in a state;

performing a Pauli-X stabilizer circuit with single qubit rotations onto each data qubit; and

measuring the at least one ancilla qubit.

11. The system of claim 10 further comprising based on the measurement result of the at least one ancilla qubit, performing an additional correction to the data qubits.

12. The system of claim 11 , wherein the additional correction comprises a X-rotation on a single qubit.

13. The system of claim 9 , wherein measuring the CZ operator comprises:

performing a Pauli-X stabilizer circuit with specific single qubit rotations onto data qubits; and

measuring the ancilla qubit.

14. The system of claim 13 further comprising:

performing at least one error detecting measurement prior to performing additional operations with the CZ state.

15. A computer program product comprising one or more processors, one or more computer readable memories, one or more computer readable storage devices, one or more computer-readable storage devices, and program instructions stored on the one or more computer readable storage devices for execution by one or more processors via the one or more memories, the program instructions comprising instructions for:

initializing, on quantum hardware, a code state across data qubits;

measuring a CZ operator of the codes state on at least one ancilla qubit proximal to the data qubits; and

based on the measurement of the at least one ancilla qubit, performing additional quantum operations with the CZ state.

16. The computer program product of claim 15 , wherein initializing the code state across data qubits comprises:

initializing each data qubit in a state;

performing a Pauli-X stabilizer circuit with single qubit rotations onto each data qubit; and

measuring the at least one ancilla qubit.

17. The computer program product of claim 16 further comprising based on the measurement result of the at least one ancilla qubit, performing an additional correction to the data qubits.

18. The computer program product of claim 17 , wherein the additional correction comprises a X-rotation on a single qubit.

19. The computer program product of claim 15 , wherein measuring the CZ operator comprises:

performing a Pauli-X stabilizer circuit with specific single qubit rotations onto data qubits; and

measuring the ancilla qubit.

20. The computer program product of claim 19 further comprising:

performing at least one error detecting measurement prior to performing additional operations with the CZ state.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 13, 2024
From: BROWN, BENJAMIN JAMES; CROSS, ANDREW W.; GUPTA, RIDDHI SWAROOP; JOCHYM-O'CONNOR, TOMAS RAPHAEL; YODER, THEODORE JAMES
To: INTERNATIONAL BUSINESS MACHINES CORPORATION
Reel/Frame 067712/0929 →
Continuity (1)
Related Publication 20240152335A1 · May 9, 2024
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