Fair sampling with temperature-targeted QAOA based on quantum-classical correspondence theory

Tetsuro Abe; Shu Tanaka

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arXiv · 2601.16144

Fair sampling with temperature-targeted QAOA based on quantum-classical correspondence theory

Tetsuro Abe·Shu Tanaka

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Abstract

In combinatorial optimization problems with degenerate ground states, fair sampling of degenerate solutions is essential. However, the quantum approximate optimization algorithm (QAOA) with a standard transverse-field mixer induces biases among degenerate states as circuit depth increases. Based on quantum-classical correspondence theory, we propose SBO-QAOA, which employs a temperature-dependent Hamiltonian encoding a Gibbs distribution as its ground state. Numerical simulations show that, unlike standard QAOA, SBO-QAOA yields ground-state probabilities converging to finite-temperature values with uniform distribution among degenerate states. These fairness and temperature-targeting properties are preserved even with only four variational parameters under a linear schedule.

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Tetsuro Abe, Shu Tanaka. 2026-01-22. Fair sampling with temperature-targeted QAOA based on quantum-classical correspondence theory. https://arxiv.org/abs/2601.16144

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