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arXiv · 2503.09356

Optimal elemental configuration search in crystal using quantum approximate optimization algorithm

Kazuhide Ichikawa·Genta Hayashi·Satoru Ohuchi·Tomoyasu Yokoyama·Ken N. Okada·Keisuke Fujii
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Abstract

Optimal elemental configuration search in crystal is a crucial task to discovering industrially important materials such as lithium-ion battery cathodes. In this paper we present application of quantum approximate optimization algorithm, the representative near-term quantum algorithm for combinatorial optimization, to finding the most stable elemental configuration in a crystal, using Au-Cu alloys as an example. After expressing the energy of the crystal in the form of the Ising model through the cluster expansion method combined with first-principles calculations, we numerically perform QAOA with three types of parameter optimization. As a result, we have demonstrated that the optimal solution can be sampled with a high probability for crystals containing up to 32 atoms. Our results could pave the way for optimal elemental configuration search in a crystal using a near-term quantum computer.

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Kazuhide Ichikawa, Genta Hayashi, Satoru Ohuchi, Tomoyasu Yokoyama, Ken N. Okada, Keisuke Fujii. 2025-03-12. Optimal elemental configuration search in crystal using quantum approximate optimization algorithm. https://arxiv.org/abs/2503.09356

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