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arXiv · 0911.0581

Fast Decoders for Topological Quantum Codes

Guillaume Duclos-Cianci·David Poulin
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Abstract

We present a family of algorithms, combining real-space renormalization methods and belief propagation, to estimate the free energy of a topologically ordered system in the presence of defects. Such an algorithm is needed to preserve the quantum information stored in the ground space of a topologically ordered system and to decode topological error-correcting codes. For a system of linear size L, our algorithm runs in time log L compared to L^6 needed for the minimum-weight perfect matching algorithm previously used in this context and achieves a higher depolarizing error threshold.

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BibTeXRIS

Guillaume Duclos-Cianci, David Poulin. 2010-02-05. Fast Decoders for Topological Quantum Codes. https://doi.org/10.1103/physrevlett.104.050504

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