K-ADAPT-VQE: Optimizing Molecular Ground State Searches by Chunking Operators
摘要
Classical simulation of molecular systems is fundamentally limited by exponential scaling, motivating the development of quantum algorithms such as the Variational Quantum Eigensolver (VQE). While the Adaptive VQE (ADAPT-VQE) improves upon VQE by dynamically constructing ansätze from an operator pool, its one-operator-at-a-time strategy can lead to high computational overhead. In this work, we introduce K-ADAPT-VQE, a generalization of ADAPT-VQE that selects operators in chunks of K per iteration, thereby accelerating convergence. Using the MIMIQ quantum simulator, we benchmark the method on \(\textrm{BeH}_2\) , LiH, and \(\textrm{N}_2\) , demonstrating that K-ADAPT-VQE consistently reduces the number of iterations and quantum function calls required to achieve chemical accuracy, with improvements of up to an order of magnitude relative to ADAPT-VQE. These findings indicate that chunked operator selection offers a scalable path for applying adaptive ansätze construction to increasingly complex molecular systems.