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arXiv · 1909.06732

On maximum-likelihood decoding with circuit-level errors

Leonid P. Pryadko
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Abstract

Error probability distribution associated with a given Clifford measurement circuit is described exactly in terms of the circuit error-equivalence group, or the circuit subsystem code previously introduced by Bacon, Flammia, Harrow, and Shi. This gives a prescription for maximum-likelihood decoding with a given measurement circuit. Marginal distributions for subsets of circuit errors are also analyzed; these generate a family of related asymmetric LDPC codes of varying degeneracy. More generally, such a family is associated with any quantum code. Implications for decoding highly-degenerate quantum codes are discussed.

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Leonid P. Pryadko. 2019-09-15. On maximum-likelihood decoding with circuit-level errors. https://doi.org/10.22331/q-2020-08-06-304

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