Fast Flux-Activated Leakage Reduction for Superconducting Quantum Circuits
Quantum computers will require quantum error correction to reach the low error rates necessary for solving problems that surpass the capabilities of conventional computers. One of the dominant errors limiting the performance of quantum error correction codes across multiple technology platforms is leakage out of the computational subspace arising from the multilevel structure of qubit implementations. Here, we present a resource-efficient universal leakage reduction unit for superconducting qubits using parametric flux modulation. This operation removes leakage down to our measurement inaccuracy of 7×10^{-4} in approximately 50 ns with a low error of 2.5(1)×10^{-3} on the computational subspace, thereby reaching durations and fidelities comparable to those of single-qubit gates. We demonstrate that using the leakage reduction unit in repeated weight-two stabilizer measurements reduces the total number of detected errors in a scalable fashion to close to what can be achieved using leakage-rejection methods that do not scale. Our approach does not require additional control electronics or on-chip components and is applicable to both auxiliary and data qubits. These benefits make our method particularly attractive for mitigating leakage in large-scale quantum error correction circuits, a crucial requirement for the practical implementation of fault-tolerant quantum computation.
Authors
- Graham J. Norris (ORCID: https://orcid.org/0000-0002-1016-9956)
- Andreas J. Wallraff (ORCID: https://orcid.org/0000-0002-3476-4485)
- Alexander Flasby (ORCID: https://orcid.org/0000-0002-1573-7537)
- Michael Kerschbaum (ORCID: https://orcid.org/0009-0003-6172-1100)
- Ross Shillito (ORCID: https://orcid.org/0000-0002-5255-1336)
- Christoph Hellings (ORCID: https://orcid.org/0000-0002-9929-9684)
- Nathan Lacroix (ORCID: https://orcid.org/0000-0003-2002-9495)
- François Swiadek (ORCID: https://orcid.org/0009-0000-2823-8246)
- Stefania Lazar
- Sebastian Krinner (ORCID: https://orcid.org/0000-0002-4388-071X)
- A. H. McDonald (ORCID: https://orcid.org/0000-0002-7257-5853)
- Ants Remm (ORCID: https://orcid.org/0000-0002-3220-7044)
- Alexandre Blais (ORCID: https://orcid.org/0000-0002-0591-2012)
- Mohsen Bahrami Panah
- Dante Colao-Zanuz
- Luca Hofele (ORCID: https://orcid.org/0009-0006-1692-1025)
- Othmane Benhayoune-Khadraoui
Institutions
- Canadian Institute for Advanced Research (CA)
- Université de Sherbrooke (CA)
- Paul Scherrer Institute (CH)
- ETH Zurich (CH)
Publication Details
- Journal
- Physical Review Letters
- Published
- 2025-03-25
- DOI
- https://doi.org/10.1103/physrevlett.134.120601
- Citations
- 18
- Primary Topic
- Quantum Computing Algorithms and Architecture
- Type
- article
- Field-Weighted Citation Impact
- 44.66
Funders
- U.S. Department of Energy
- Office of the Director of National Intelligence
- European Commission
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Eidgenössische Technische Hochschule Zürich
- Canada First Research Excellence Fund
- ETH Zürich Foundation
- Intelligence Advanced Research Projects Activity
- Natural Sciences and Engineering Research Council of Canada
- National Center of Competence in Research Quantum Science and Technology
- Army Research Office