Work extraction from coherently activated maps via quantum switch

Kyrylo Simonov, Gianluca Francica, Giacomo Guarnieri, Mauro Paternostro

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25 Citations (Scopus)
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We characterize the impact that the application of two maps in a quantum-controlled order has on the process of work extraction via unitary cycles and its optimization. The control is based on the quantum switch model that applies maps in an order not necessarily compatible with the underlying causal structure and, in principle, can be implemented experimentally. First, we show that the activation of quantum maps through the quantum switch model always entails a non-negative gain in ergotropy compared to their consecutive application. We also establish a condition that the maps should fulfill in order to achieve a nonzero ergotropic gain. We then perform a thorough analysis of maps applied to a two-level system and provide general conditions for achieving a positive gain on the incoherent part of ergotropy. Our results are illustrated with several examples and applied to qubit and d-dimensional quantum systems. In particular, we demonstrate that a nonzero work can be extracted from a system thermalized by two coherently controlled reservoirs.

Original languageEnglish
Article number032217
JournalPhysical Review A
Issue number3
Publication statusPublished - 31 Mar 2022

Bibliographical note

Funding Information:
We are grateful to Časlav Brukner, Giulio Chiribella, Philippe Allard Guérin, Tamal Guha, Hlér Kristjánsson, Ilya Kull, Gonzalo Manzano, Giulia Rubino, Roy Saptarshi, Uttam Singh, and Zoltán Zimborás for the fruitful discussions and three anonymous referees for the useful and valuable comments to the manuscript. We acknowledge support from the Austrian Science Fund (Grant No. FWF-P30821), the European Research Council Starting Grant ODYSSEY (Grant No. 758403), the H2020-FETOPEN-2018-2020 project TEQ (Grant No. 766900), the DfE-SFI Investigator Programme (Grant No. 15/IA/2864), COST Action CA15220, the Royal Society Wolfson Research Fellowship (RSWF/R3/183013) and International Exchanges Programme (IEC/R2/192220), the Leverhulme Trust Research Project Grant (Grant No. RGP-2018-266), the UK EPSRC (EP/T028424/1), and the Department for the Economy Northern Ireland under the US-Ireland R&D Partnership Programme (USI 175). G.G. acknowledges support from FQXi and DFG FOR2724 and also from the European Union Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 101026667.

Publisher Copyright:
© 2022 American Physical Society.

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics


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