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arXiv · 2109.13043

Optimal quantum annealing: A variational shortcut to adiabaticity approach

Gianluca Passarelli·Rosario Fazio·Procolo Lucignano
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Abstract

Suppressing unwanted transitions out of the instantaneous ground state is a major challenge in unitary adiabatic quantum computation. A recent approach consists in building counterdiabatic potentials approximated using variational strategies. In this contribution, we extend this variational approach to Lindbladian dynamics, having as a goal the suppression of diabatic transitions between pairs of Jordan blocks in quantum annealing. We show that, surprisingly, unitary counterdiabatic ans\"atze are successful for dissipative dynamics as well, allowing for easier experimental implementations compared to Lindbladian ans\"atze involving dissipation. Our approach not only guarantees improvements of open-system adiabaticity but also enhances the success probability of quantum annealing.

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Gianluca Passarelli, Rosario Fazio, Procolo Lucignano. 2021-09-27. Optimal quantum annealing: A variational shortcut to adiabaticity approach. https://doi.org/10.1103/physreva.105.022618

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