Quantum device facilitating suppression of ZZ interactions between two-junction superconducting qubits

Patent metadata

Field	Value
Publication number	US-11587976-B2
Application number	US-202016917056-A
Country	US
Kind code	B2
Filing date	Jun 30, 2020
Priority date	Jun 30, 2020
Publication date	Feb 21, 2023
Grant date	Feb 21, 2023

Abstract

Devices and/or computer-implemented methods facilitating static ZZ suppression and Purcell loss reduction using mode-selective coupling in two-junction superconducting qubits are provided. In an embodiment, a device can comprise a superconducting bus resonator. The device can further comprise a first superconducting qubit. The device can further comprise a second superconducting qubit, the first superconducting qubit and the second superconducting qubit respectively comprising: a first superconducting pad; a second superconducting pad; a third superconducting pad; a first Josephson Junction coupled to the first superconducting pad and the second superconducting pad; and a second Josephson Junction coupled to the second superconducting pad and the third superconducting pad. The first superconducting pad and the second superconducting pad of the first superconducting qubit and the second superconducting qubit are coupled to the superconducting bus resonator. The superconducting bus resonator entangles the first superconducting qubit and the second superconducting qubit based on receiving a control signal.

First claim

What is claimed is:

1. A computer-implemented method, comprising:
encoding, by a system operatively coupled to a processor, quantum information in a first oscillating mode of a first superconducting qubit and a second superconducting qubit; and
coupling, by the system, a superconducting bus resonator to an oscillating mode structure corresponding to a second oscillating mode of the first superconducting qubit and the second superconducting qubit.

2. The computer-implemented method of claim 1 , wherein the first superconducting qubit operates in the first oscillating mode and the second oscillating mode.

3. The computer-implemented method of claim 1 , wherein the second superconducting qubit operates in the first oscillating mode and the second oscillating mode.

4. The computer-implemented method of claim 1 , wherein at least one of the first superconducting qubit or the second superconducting qubit comprises at least one of a tunable coupler qubit, a two junction qubit, a multimode qubit, a multimode two junction qubit, or a tunable qubit.

5. The computer-implemented method of claim 1 , further comprising:
encoding, by the system, the quantum information in the first oscillating mode of the first superconducting qubit and the second superconducting qubit; and
coupling, by the system, the superconducting bus resonator to the oscillating mode structure corresponding to the second oscillating mode of the first superconducting qubit and the second superconducting qubit to suppress ZZ interactions between the first superconducting qubit and the second superconducting qubit and to reduce energy loss associated with the superconducting bus resonator, thereby facilitating at least one of: reduced quantum gate errors associated with at least one of the first superconducting qubit or the second superconducting qubit; increased speed of a quantum gate comprising the first superconducting qubit and the second superconducting qubit; or at least one of improved fidelity, improved accuracy, or improved performance of a quantum processor comprising the first superconducting qubit, the second superconducting qubit, and the superconducting bus resonator.

6. A computer-implemented method, comprising:
encoding, by a system operatively coupled to a processor, quantum information in a data mode of a first superconducting qubit and a second superconducting qubit; and
coupling, by the system, a superconducting bus resonator to a coupling mode structure corresponding to a coupling mode of the first superconducting qubit and the second superconducting qubit.

7. The computer-implemented method of claim 6 , wherein the first superconducting qubit operates in the data mode and the coupling mode.

8. The computer-implemented method of claim 6 , wherein the second superconducting qubit operates in the data mode and the coupling mode.

9. The computer-implemented method of claim 6 , wherein at least one of the first superconducting qubit or the second superconducting qubit comprises at least one of a tunable coupler qubit, a two junction qubit, a multimode qubit, a multimode two junction qubit, or a tunable qubit.

10. The computer-implemented method of claim 6 , further comprising:
encoding, by the system, the quantum information in the data mode of the first superconducting qubit and the second superconducting qubit; and
coupling, by the system, the superconducting bus resonator to the coupling mode structure corresponding to the coupling mode of the first superconducting qubit and the second superconducting qubit to suppress ZZ interactions between the first superconducting qubit and the second superconducting qubit and to reduce energy loss associated with the superconducting bus resonator, thereby facilitating at least one of: reduced quantum gate errors associated with at least one of the first superconducting qubit or the second superconducting qubit; increased speed of a quantum gate comprising the first superconducting qubit and the second superconducting qubit; or at least one of improved fidelity, improved accuracy, or improved performance of a quantum processor comprising the first superconducting qubit, the second superconducting qubit, and the superconducting bus resonator.

Assignees

• IBM

Inventors

• Finck Aaron
• Carniol April
• Blair John

Classifications

• G06N10/20

  Models of quantum computing, e.g. quantum circuits or universal quantum computers · CPC title

• G06N10/70 Primary

  Quantum error correction, detection or prevention, e.g. surface codes or magic state distillation · CPC title

• G06N10/40 Primary

  Physical realisations or architectures of quantum processors or components for manipulating qubits, e.g. qubit coupling or qubit control · CPC title

• H01P3/003 Primary

  Coplanar lines · CPC title

• B82Y10/00

  Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic · CPC title