Improved quantum processor logical error rates via correction and detection

Abstract Performing quantum algorithms for critical problems in physics and chemistry requires substantially lower error rates than the physical error rates of present quantum computers. Achieving such low logical error rates requires quantum error correction1,2 and physical error rates below a critical threshold value3,4,5,6,7,8. We experimentally demonstrate on a trapped-ion quantum charge-coupled device (QCCD)9,10 improvements in logical error rates ranging from 11× to 800× compared with several physical circuit baselines, including quantum computation on multiple qubits. Our results hinge on two quantum error correction code constructions optimized for an ion-trap processor: a 12-qubit code encoding two qubits inspired by Knill11 and a 16-qubit tesseract colour code encoding four qubits12,13. These constructions are combined with a scalable method of error detection and post-selection to achieve reduced logical error rates. Our results show that state-of-the-art quantum devices are already able to make use of fault tolerance and error correction to strongly suppress errors in non-trivial quantum circuit computations. This is a preview of subscription content, access via your institution Access options Access Nature and 54 other Nature Portfolio journals Get Nature+, our best-value online-access subscription £17.99 / 30 days cancel any time Subscribe to this journal Receive 52 print issues and online access £199.00 per year only £3.83 per issue Buy this article - Purchase on SpringerLink - Instant access to the full article PDF. £ 29.95 Prices may be subject to local taxes which are calculated during checkout Data availability The data from the experimental runs are available on request. Code availability The quantum circuits used in these experiments are available on request. References Reiher, M., Wiebe, N., Svore, K. M., Wecker, D. & Troyer, M. Elucidating reaction mechanisms on quantum computers. 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B.W.R. designed and analysed the tesseract code experiments. C.R.-A., J.P.C., A.C., J.M.D., C.F., J.P.G., T.M.G., D.G., D.H., N.H., C.H., C.V.H., J.J., D.L., Y.M., M.M., S.A.M., B.N., J.P., P.S. and R.P.S. engineered the hardware and its execution, the compilation tools and dynamic decoupling algorithms. C.R.-A. designed and analysed the Steane code experiments. All authors evaluated the results. A. Paetznick, B.W.R., M.P.d.S., C.R.-A., D.H., B.N., R.P.S. and K.M.S. wrote the manuscript and collected inputs from all of the other authors. Corresponding author Ethics declarations Competing interests A.P., B.W.R., M.P.d.S., D.A., J.M.B.-R., R.C., W.v.D., L.G.-S., A.P., A.S., D.T., Z.W., S.J.W., M.Z. and K.M.S. were employees of Microsoft at the time of performing the experiments and writing the manuscript. C.R.-A., J.P.C., A.C., J.M.D., C.F., J.P.G., T.M.G., D.G., D.H., N.H., C.H., C.V.H., J.J., D.L., Y.M., M.M., S.A.M., B.N., J.P., P.S. and R.P.S. were employees of Quantinuum at the time of performing the experiments and writing the manuscript. Peer review Peer review information Additional information Supplementary information Supplementary Information (download PDF ) Supplementary Information, including Supplementary Figs. 1–14, Supplementary Tables 1–7 and Supplementary References. Rights and permissions About this article Cite this article Paetznick, A., Reichardt, B.W., Silva, M.P.d. et al. Improved quantum processor logical error rates via correction and detection. Nature 654, 349–355 (2026). https://doi.org/10.1038/s41586-026-10628-y Received: Accepted: Published: Version of record: Issue date: DOI: https://doi.org/10.1038/s41586-026-10628-y