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Efficiency of Inefficient Endoreversible Thermal Machines


We present a study of the performance of endoreversible thermal machines optimized with respect to the thermodynamic force associated with the cold bath in the regime of small thermodynamic forces. These thermal machines can work either as an engine or as a refrigerator. We analyze how the optimal performances are determined by the dependence of the thermodynamic flux on the forces. The results are motivated and illustrated with a quantum model, the three level maser, and explicit analytical expressions of the engine efficiency as a function of the system parameters are given.

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D. Alonso acknowledges the warm hospitality and support of the organizing committee of the Quantum Information and Thermodynamics workshop held in São Carlos in February 2015 and to Prof. Lucas C. Céleri for his kind assistance. We thank R. Kosloff, R. Uzdin, M Esposito, A del Campo, and I. de Vega for fruitful discussions in São Carlos. Financial support from Spanish MINECO (FIS2013-40627-P and FIS2013-41352-P), COST Action MP1209, and EU Collaborative Project TherMiQ (Grant Agreement 618074) is gratefully acknowledged.

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Correspondence to Daniel Alonso.

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Palao, J.P., Correa, L.A., Adesso, G. et al. Efficiency of Inefficient Endoreversible Thermal Machines. Braz J Phys 46, 282–287 (2016).

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  • Efficiency
  • Quantum thermodynamics
  • Endoreversible