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arXiv · 2506.09658

K-ADAPT-VQE: Optimizing Molecular Ground State Searches by Chunking Operators

Tatiana A. Bespalova·Oumaya Ladhari·Guido Masella
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Abstract

Classical simulation of molecular systems is limited by exponential scaling, a hurdle quantum algorithms like Variational Quantum Eigensolvers (VQEs) aim to overcome. Although ADAPT-VQE enhances VQEs by dynamically building ans\"atze, it can remain computationally intensive. This work presents K-ADAPT-VQE, which improves efficiency by adding operators in chunks of K at each iteration. Our results from simulating small molecular systems show that K-ADAPT-VQE substantially reduces the total number of VQE iterations and quantum function calls required to achieve chemical accuracy in molecular ground state calculations.

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Tatiana A. Bespalova, Oumaya Ladhari, Guido Masella. 2025-06-11. K-ADAPT-VQE: Optimizing Molecular Ground State Searches by Chunking Operators. https://arxiv.org/abs/2506.09658

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