Quantum Error Correction with High Rate Codes

ORAL  · Invited

Abstract

Quantum low-density parity-check (qLDPC) codes have emerged as a compelling route to scalable, fault-tolerant quantum computation and communication with dramatically reduced overheads compared to surface-code architectures. In this talk, I will present a unified perspective on recent advances in high-rate qLDPC coding and their implications for large-scale quantum computation. First, we show how high-rate qLDPC codes can be implemented on realistic hardware platforms such as reconfigurable neutral atom arrays [1, 5]. We then explore universal operations enabled by high-rate, high-distance qLDPC codes [3, 4]. In particular, finite-block-length "tricycle" codes support constant-depth logical CCZ gates across three code blocks, enabling direct magic-state generation and single-shot error correction with logical error rates on the order of 10^(-10). This achieves full universality without the large overheads of conventional magic-state distillation. We further introduce new neural decoders for qLDPC codes [6]. Applied to bivariate bicycle codes, these decoders reach the highest logical accuracies reported to date, exhibiting no observed error floors down to very low logical error rates - addressing a long-standing limitation of machine-learning-based decoders. Finally, we extend qLDPC techniques to distributed quantum computing [2] and conclude with a discussion of the challenges and opportunities for realizing practical high-rate qLDPC quantum architectures.

*We acknowledge financial support from IARPA and the Army Research Office, under the Entangled Logical Qubits program (Cooperative Agreement Number W911NF-23-2-0219), the DARPA MeasQuIT program (grant number HR0011-24-9-0359), the Center for Ultracold Atoms (a NSF Physics Frontiers Center, PHY-1734011), the National Science Foundation (grant numbers PHY-2012023 and  CCF-2313084).

Publication: [1] Q. Xu*, JPBA*, C. A. Pattison, N. Raveendran, D. Bluvstein, J. Wurtz, B. Vasic, M. D. Lukin, L. Jiang, H. Zhou, "Constant-Overhead Fault-Tolerant Quantum Computation with Reconfigurable Atom Arrays" (Nature Physics 2024)
[2] JPBA, H. Zhou, Q. Xu, G. Baranes, B. Li, M. D. Lukin, L. Jiang, "Constant-Overhead Fault-Tolerant Bell-Pair Distillation using High-Rate Codes" (PRL 2025)
[3] Q. Xu, H. Zhou, G. Zheng, D. Bluvstein, JPBA, M. D. Lukin, L. Jiang, "Fast and Parallelizable Logical Computation with Homological Product Codes", (PRX 2025)
[4] V. Menon*, JPBA*, R. Mehta, A. Gu, D. B. Tan, M. D. Lukin, "Magic tricycles: Efficient magic state generation with finite block-length quantum LDPC codes" (arXiv 2025)
[5] D. B. Tan, JPBA, V. Menon, J. M. Koh, A. C. Diaconu, M. D. Lukin, "Syndrome Extraction Circuits with Near-Optimal Depths for Practical Quantum Error Correcting Code Families" (In preparation)
[6] A. Gu, JPBA, et al. "Scaling Neural Decoders to Large Codes and Low Error Rates" (In preparation)

Presenters

  • J. Pablo Bonilla Ataides

    • Harvard

Authors

  • J. Pablo Bonilla Ataides

    • Harvard
  • Varun Menon

    • Harvard
  • Andi Gu

    • Harvard
  • Qian Xu

    • Caltech
    • California Institute of Technology
  • Christopher Pattison

    • Caltech
  • Daniel B Tan

    • Harvard University
    • Harvard
  • Hengyun Zhou

    • QuEra Computing Inc.
    • QuEra Computing Inc., Massachusetts Institute of Technology
    • QuEra Computing and MIT
  • Nithin Raveendran

    • Arizona
  • Dolev Bluvstein

    • Harvard University
    • California Institute of Technology
  • Gefen Baranes

    • Massachusetts Institute of Technology
  • Andrei C Diaconu

    • Harvard University
    • Harvard Quantum Initiative
  • Guo Zheng

    • University of Chicago
  • Rohan Mehta

    • Harvard
  • Jonathan R Wurtz

    • Boston University
  • Bikun Li

    • University of Chicago
  • Jin Ming Koh

    • Harvard University
  • Bane Vasic

    • Arizona
  • Susanne F Yelin

    • Harvard University
  • Liang Jiang

    • University of Chicago
  • Mikhail D Lukin

    • Harvard University