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arXiv · 2604.25715

Ground-state energies of Ising models calculated using the samples from a quantum computer that simulates short-time evolution

John P. T. Stenger·C. Stephen Hellberg·Daniel Gunlycke
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Abstract

We find the ground-state energy of the Ising model using the Cascaded Variational Quantum Eigensolver (CVQE) algorithm with the Guided-Sampling Ansatz (GSA) using up to 63 qubits on a quantum computer. We study a heavy-hex lattice to match the qubit architecture, allowing us to perform calculations in the quantum utility regime. We study both a homogeneous and random-coupling model. We locate the boundary of acceptable quantum errors as a function of the number of qubits and coupling strength. An entropic analysis is performed giving insights into the quantum computing performance. A subspace analysis is performed that suggests that the Ising model is especially suited for near-term quantum computing.

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John P. T. Stenger, C. Stephen Hellberg, Daniel Gunlycke. 2026-04-28. Ground-state energies of Ising models calculated using the samples from a quantum computer that simulates short-time evolution. https://arxiv.org/abs/2604.25715

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