We show a significant reduction of errors for an architecture of quantum annealers (QA) where bosonic modes mediate the interaction between qubits. These systems have a large redundancy in the subspace of solutions, supported by arbitrarily large bosonic occupations. We explain how this redundancy leads to a mitigation of errors when the bosonic modes operate in the ultrastrong coupling regime. Numerical simulations also predict a large increase of qubit coherence for a specific annealing problem with mediated interactions. We provide evidences that noise reduction occurs in more general types of quantum computers with similar architectures.
@article{arxiv.1910.13459,
title = {Mediator assisted cooling in quantum annealing},
author = {M. Pino and Juan José García-Ripoll},
journal= {arXiv preprint arXiv:1910.13459},
year = {2020}
}