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arXiv · 1404.5504

Single-shot fault-tolerant quantum error correction

H. Bombin
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Abstract

Conventional quantum error correcting codes require multiple rounds of measurements to detect errors with enough confidence in fault-tolerant scenarios. Here I show that for suitable topological codes a single round of local measurements is enough. This feature is generic and is related to self-correction and confinement phenomena in the corresponding quantum Hamiltonian model. 3D gauge color codes exhibit this single-shot feature, which applies also to initialization and gauge-fixing. Assuming the time for efficient classical computations negligible, this yields a topological fault-tolerant quantum computing scheme where all elementary logical operations can be performed in constant time.

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H. Bombin. 2014-04-22. Single-shot fault-tolerant quantum error correction. https://doi.org/10.1103/physrevx.5.031043

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