| Title: |
Simplified circuit-level decoding using Knill error correction |
| Authors: |
Murphy, Ewan; Sahu, Subhayan; Vasmer, Michael |
| Contributors: |
Cryptologie symétrique, cryptologie fondée sur les codes et information quantique (COSMIQ); Centre Inria de Paris; Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria); Quandela SAS; Perimeter Institute for Theoretical Physics Waterloo; Institute for Quantum Computing Waterloo (IQC); University of Waterloo Waterloo; EM gratefully acknowledges the financial support of NTT Research while working in Waterloo. Research at IQC and the Perimeter Institute is supported in part by the Government of Canada through the Department of Innovation, Science and Economic Development; and by the Province of Ontario through the Ministry of Colleges, Universities, Research Excellence and Security. This work was co-funded by CIFRE grant n°2025/0667.; ANR-22-PETQ-0006,NISQ2LSQ,From NISQ to LSQ: Bosonic and LDPC codes(2022) |
| Source: |
https://hal.science/hal-05568322 ; 2026. |
| Publisher Information: |
CCSD |
| Publication Year: |
2026 |
| Subject Terms: |
Quantum Physics (quant-ph); FOS: Physical sciences; [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph] |
| Description: |
Quantum error correction will likely be essential for building a large-scale quantum computer, but it comes with significant requirements at the level of classical control software. In particular, a quantum error-correcting code must be supplemented with a fast and accurate classical decoding algorithm. Standard techniques for measuring the parity-check operators of a quantum error-correcting code involve repeated measurements, which both increases the amount of data that needs to be processed by the decoder, and changes the nature of the decoding problem. Knill error correction is a technique that replaces repeated syndrome measurements with a single round of measurements, but requires an auxiliary logical Bell state. Here, we provide a theoretical and numerical investigation into Knill error correction from the perspective of decoding. We give a self-contained description of the protocol, prove its fault tolerance under locally decaying (circuit-level) noise, and numerically benchmark its performance for quantum low-density parity-check codes. We show analytically and numerically that the time-constrained decoding problem for Knill error correction can be solved using the same decoder used for the simpler code-capacity noise model, illustrating that Knill error correction may alleviate the stringent requirements on classical control required for building a large-scale quantum computer. |
| Document Type: |
report |
| Language: |
English |
| Relation: |
info:eu-repo/semantics/altIdentifier/arxiv/2603.05320; ARXIV: 2603.05320 |
| DOI: |
10.48550/arXiv.2603.05320 |
| Availability: |
https://hal.science/hal-05568322; https://doi.org/10.48550/arXiv.2603.05320 |
| Accession Number: |
edsbas.5A03EBAB |
| Database: |
BASE |