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arXiv · 2510.08864

Optimizing VQE Ansatz for Studying Tight-Binding Models with \textit{sd}-Interaction and On-Site Coulomb Repulsion

Oleg Udalov
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Abstract

The VQE algorithm is applied to the problem of finding the ground state of a lattice model with on-site Coulomb repulsion, nearest-neighbor hopping, and on-site sd-interaction. We compare the performance of several ansatze, including cluster and generic forms. Several modifications of the standard cluster ansatz implementation are proposed, which significantly reduce the number of two-qubit gates. Different classical optimizers are employed within the VQE algorithm. The performance of the algorithms is evaluated using both noiseless and noisy simulations.

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Oleg Udalov. 2025-10-09. Optimizing VQE Ansatz for Studying Tight-Binding Models with \textit{sd}-Interaction and On-Site Coulomb Repulsion. https://arxiv.org/abs/2510.08864

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