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arXiv · 2203.14756

Reference-State Error Mitigation: A Strategy for High Accuracy Quantum Computation of Chemistry

Phalgun Lolur·Mårten Skogh·Christopher Warren·Janka Biznárová·Amr Osman·Giovanna Tancredi·Göran Wendin·Jonas Bylander·Martin Rahm
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Abstract

Decoherence and gate errors severely limit the capabilities of state-of-the-art quantum computers. This work introduces a strategy for reference-state error mitigation (REM) of quantum chemistry that can be straightforwardly implemented on current and near-term devices. REM can be applied alongside existing mitigation procedures, while requiring minimal post-processing and only one or no additional measurements. The approach is agnostic to the underlying quantum mechanical ansatz and is designed for the variational quantum eigensolver (VQE). Two orders-of-magnitude improvement in the computational accuracy of ground state energies of small molecules (H2, HeH+ and LiH) is demonstrated on superconducting quantum hardware. Simulations of noisy circuits with a depth exceeding 1000 two-qubit gates are used to argue for scalability of the method.

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Phalgun Lolur, Mårten Skogh, Christopher Warren, Janka Biznárová, Amr Osman, Giovanna Tancredi, Göran Wendin, Jonas Bylander, Martin Rahm. 2022-03-28. Reference-State Error Mitigation: A Strategy for High Accuracy Quantum Computation of Chemistry. https://arxiv.org/abs/2203.14756

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