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Quantum Consensus Dynamics by Entangling Maxwell Demon

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 نشر من قبل Sungguen Ryu
 تاريخ النشر 2021
  مجال البحث فيزياء
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We introduce a Maxwell demon which generates many-body-entanglement robustly against thermal fluctuations, which allows us to obtain quantum advantage. Adopting the protocol of the voter model used for opinion dynamics approaching consensus, the demon randomly selects a qubit pair and performs a quantum feedback control, in continuous repetitions. We derive a lower bound of the entropy production rate by demons operation, which is determined by a competition between the quantum-classical mutual information acquired by the demon and the absolute irreversibility of the feedback control. Our finding of the lower bound corresponds to a reformulation of the second law of thermodynamics under a stochastic and continuous quantum feedback control.



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