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DOE OSTI · 2008288

Lower Bounds on Quantum Annealing Times

García-Pintos, Luis Pedro·Brady, Lucas T.·Bringewatt, Jacob·Liu, Yi-Kai
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Abstract

The adiabatic theorem provides sufficient conditions for the time needed to prepare a target ground state. While it is possible to prepare a target state much faster with more general quantum annealing protocols, rigorous results beyond the adiabatic regime are rare. Here, we provide such a result, deriving lower bounds on the time needed to successfully perform quantum annealing. The bounds are asymptotically saturated by three toy models where fast annealing schedules are known: the Roland and Cerf unstructured search model, the Hamming spike problem, and the ferromagnetic p-spin model. Our bounds demonstrate that these schedules have optimal scaling. Herein, our results also show that rapid annealing requires coherent superpositions of energy eigenstates, singling out quantum coherence as a computational resource.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSAdiabatic quantum optimizationQuantum Information, Science & TechnologyQuantum algorithmsQuantum computation

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García-Pintos, Luis Pedro, Brady, Lucas T., Bringewatt, Jacob, Liu, Yi-Kai. 2023-04-05. Lower Bounds on Quantum Annealing Times. https://doi.org/10.1103/physrevlett.130.140601

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