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arXiv · 2201.03358

Quantum Approximate Optimization Algorithm pseudo-Boltzmann states

Pablo Díez-Valle·Diego Porras·Juan José García-Ripoll
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Abstract

In this letter, we provide analytical and numerical evidence that the single-layer Quantum Approximate Optimization Algorithm (QAOA) on universal Ising spin models produces thermal-like states. We find that these pseudo-Boltzmann states can not be efficiently simulated on classical computers according to the general state-of-the-art condition that ensures rapid mixing for Ising models. Moreover, we observe that the temperature depends on a hidden universal correlation between the energy of a state and the covariance of other energy levels and the Hamming distances of the state to those energies.

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Pablo Díez-Valle, Diego Porras, Juan José García-Ripoll. 2023-02-03. Quantum Approximate Optimization Algorithm pseudo-Boltzmann states. https://doi.org/10.1103/physrevlett.130.050601

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