Dithered Belief Propagation for Real-Time Quantum Memory Decoding

By Cai, Jarkas, Zhao +1Nov 4, 2026

Score████░░░░░░4.3

Key numbers

98% fewer multiplications on average

Caveats

Preprint; not yet peer reviewed.

VerdictWorth a reader's time today.

Read the original PDF

Abstract

We introduce dithered belief-propagation decoding for circuit-level quantum memory to mitigate the oscillations and trapping behavior that limit standard belief-propagation (BP) decoders for qLDPC codes. Our approach combines a quantum-adapted sign-flip mechanism with chained randomized prior perturbation. Evaluated under circuit-level noise on the distance-11 rotated surface code and the distance-12 bivariate-bicycle code, the proposed dithered decoder significantly outperforms BP and BP+OSD+CS-10. The proposed decoder achieves accuracy comparable to or better than state-of-the-art Relay-BP, especially at higher physical error rates, while trading a moderate increase in additions for about 98% fewer multiplications on average and eliminating node-level RNGs. These results suggest that dithering is a promising approach toward real-time decoding of quantum memories.

Zhengyu Cai, Mohamad Ali Jarkas, Bokun Zhao, Warren J. Gross

The editor's rubric

Heuristic review

Leverage3 / 5: A method or resource many groups across the field will adopt within a year.; 18% of this desk’s rubric
Magnitude4 / 5: A qualitative jump: a capability or regime that did not exist before.; 20% of this desk’s rubric
Evidence3 / 5: Solid: multiple benchmarks or cohorts, ablations, fair baselines, released code or data.; 22% of this desk’s rubric
Novelty2 / 5: A new combination of known ideas.; 22% of this desk’s rubric
Trajectory2 / 5: Some room to improve with obvious engineering.; 10% of this desk’s rubric
Stakes2 / 5: Benefits a professional community (practitioners, clinicians, engineers).; 8% of this desk’s rubric

Dimension	Level	Weight	What that level means
Leverage	███░░3/5	18%	A method or resource many groups across the field will adopt within a year.
Magnitude	████░4/5	20%	A qualitative jump: a capability or regime that did not exist before.
Evidence	███░░3/5	22%	Solid: multiple benchmarks or cohorts, ablations, fair baselines, released code or data.
Novelty	██░░░2/5	22%	A new combination of known ideas.
Trajectory	██░░░2/5	10%	Some room to improve with obvious engineering.
Stakes	██░░░2/5	8%	Benefits a professional community (practitioners, clinicians, engineers).

Editor’s rationale

Heuristic triage from title and abstract text only, not a reading of the paper. Cues found: method (we propose); gains (relative gain, state of the art, outperforms); design (randomized).

How the score was computed

rank-2026-10-18

Score████░░░░░░4.3

Score = 10 × (75% × adjusted merit / 10 + 15% × attention + 10% × freshness)

Desks place stronger verdicts first, then use this score to order work within the same verdict.

Merit: 5.6 / 10; Weighted rubric, evidence-gated.
Adjusted merit: 4.6 / 10; Shrunk toward the desk prior by editor confidence (40%).
Attention: 0%; Citations, upvotes, points, mentions.
Freshness: 87%; Half-life decay since publication.

No attention signals recorded yet.

The record

Reviewed by heuristic-v10 on Nov 6, 2026, 07:29 UTC. Paper type: method.
Categories: quant-ph, cs.IT
TOP, No.5 in the Physics edition of November 6, 2026.