Pipelined correlated minimum weight perfect matching of the surface code
Abstract
We describe a pipeline approach to decoding the surface code using minimum weight perfect matching, including taking into account correlations between detection events. An independent no-communication parallelizable processing stage reweights the graph according to likely correlations, followed by another no-communication parallelizable stage for high confidence matching. A later general stage finishes the matching. This is a simplification of previous correlated matching techniques which required a complex interaction between general matching and re-weighting the graph. Despite this simplification, which gives correlated matching a better chance of achieving real-time processing, we find the logical error rate practically unchanged. We validate the new algorithm on the fully fault-tolerant toric, unrotated, and rotated surface codes, all with standard depolarizing noise. We expect these techniques to be applicable to a wide range of other decoders.
Cite
@article{arxiv.2205.09828,
title = {Pipelined correlated minimum weight perfect matching of the surface code},
author = {Alexandru Paler and Austin G. Fowler},
journal= {arXiv preprint arXiv:2205.09828},
year = {2023}
}