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arXiv · 2305.01097

Unitary Coupled Cluster: Seizing the Quantum Moment

Ilias Magoulas·Francesco A. Evangelista
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Abstract

Shallow, CNOT-efficient quantum circuits are crucial for performing accurate computational chemistry simulations on current noisy quantum hardware. Here, we explore the usefulness of non-iterative energy corrections, based on the method of moments of coupled-cluster theory, for accelerating convergence toward full configuration interaction. Our preliminary numerical results relying on iteratively constructed ans\"{a}tze suggest that chemically accurate energies can be obtained with substantially more compact circuits, implying enhanced resilience to gate and decoherence noise.

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Ilias Magoulas, Francesco A. Evangelista. 2023-05-01. Unitary Coupled Cluster: Seizing the Quantum Moment. https://doi.org/10.1021/acs.jpca.3c02781

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