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arXiv · 2309.11673

Error mitigation via error detection using Generalized Superfast Encodings

Tobias Hagge·Nathan Wiebe
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Abstract

We provide a new approach to error mitigation for quantum chemistry simulation that uses a Bravyi-Kitaev Superfast encoding to implement a quantum error detecting code within the fermionic encoding. Our construction has low-weight parity checks as well. We show that for the spinless Hubbard model with nearest-neighbor repulsion terms, one-qubit errors are detectable, and more complicated errors are detectable with high probability. While our error-detection requires additional quantum circuitry, we argue that there is a regime in which the beneficial effect of error-mitigation outweighs the deleterious effects of additional errors due to additional circuitry. We show that our scheme can be implemented under realistic qubit connectivity requirements.

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Tobias Hagge, Nathan Wiebe. 2023-09-20. Error mitigation via error detection using Generalized Superfast Encodings. https://arxiv.org/abs/2309.11673

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