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arXiv · 2112.08490

The three phases of quantum annealing: fast, slow, and very slow

Artur Soriani·Pierre Nazé·Marcus V. S. Bonança·Bartłomiej Gardas·Sebastian Deffner
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Abstract

Currently, existing quantum annealers have proven themselves as viable technology for the first practical applications in the noisy-intermediate-scale-quantum era. However, to fully exploit their capabilities, a comprehensive characterization of their finite-time excitations is instrumental. To this end, we develop a phase diagram for driven Ising chains, from which the scaling behavior of the excess work can be read off as a function of process duration and system size. "Fast" processes are well described by the Kibble-Zurek mechanism; "slow" processes are governed by effective Landau-Zener dynamics; and "very slow" processes can be approximated with adiabatic perturbation theory.

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Artur Soriani, Pierre Nazé, Marcus V. S. Bonança, Bartłomiej Gardas, Sebastian Deffner. 2021-12-15. The three phases of quantum annealing: fast, slow, and very slow. https://doi.org/10.1103/physreva.105.042423

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