Bacon-Shor Board Games

M. Sohaib Alam; Jun Zen; Thomas R. Scruby

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arXiv · 2504.02749

Bacon-Shor Board Games

M. Sohaib Alam·Jun Zen·Thomas R. Scruby

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Abstract

We identify a period-4 measurement schedule for the checks of the Bacon-Shor code that fully covers spacetime with constant-weight detectors, and is numerically observed to provide the code with a threshold. Unlike previous approaches, our method does not rely on code concatenation and instead arises as the solution to a coloring game on a square grid. Under a uniform circuit-level noise model, we observe a threshold of approximately $0.3\%$ when decoding with minimum weight perfect matching, and we conjecture that this could be improved using a more tailored decoder.

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M. Sohaib Alam, Jun Zen, Thomas R. Scruby. 2025-04-03. Bacon-Shor Board Games. https://arxiv.org/abs/2504.02749

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