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arXiv · 2308.00369

Quantum error correction with an Ising machine under circuit-level noise

Jun Fujisaki·Kazunori Maruyama·Hirotaka Oshima·Shintaro Sato·Tatsuya Sakashita·Yusaku Takeuchi·Keisuke Fujii
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Abstract

Efficient decoding to estimate error locations from outcomes of syndrome measurement is the prerequisite for quantum error correction. Decoding in presence of circuit-level noise including measurement errors should be considered in case of actual quantum computing devices. In this work, we develop a decoder for circuit-level noise that solves the error estimation problems as Ising-type optimization problems. We confirm that the threshold theorem in the surface code under the circuitlevel noise is reproduced with an error threshold of approximately 0.4%. We also demonstrate the advantage of the decoder through which the Y error detection rate can be improved compared with other matching-based decoders. Our results reveal that a lower logical error rate can be obtained using our algorithm compared with that of the minimum-weight perfect matching algorithm.

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Jun Fujisaki, Kazunori Maruyama, Hirotaka Oshima, Shintaro Sato, Tatsuya Sakashita, Yusaku Takeuchi, Keisuke Fujii. 2023-08-01. Quantum error correction with an Ising machine under circuit-level noise. https://arxiv.org/abs/2308.00369

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