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Thermodynamic bounds on efficiency for systems with broken time-reversal symmetry
Giuliano Benenti1, Keiji Saito, Giulio Casati
1CNISM, CNR-INFM & Center for Nonlinear and Complex Systems, Università degli Studi dell'Insubria, Como, Italy.
Abstract:
We show that for systems with broken time-reversal symmetry the maximum efficiency and the efficiency at maximum power are both determined by two parameters: a "figure of merit" and an asymmetry parameter. In contrast to the time-symmetric case, the figure of merit is bounded from above; nevertheless the Carnot efficiency can be reached at lower and lower values of the figure of merit and far from the so-called strong coupling condition as the asymmetry parameter increases. Moreover, the Curzon-Ahlborn limit for efficiency at maximum power can be overcome within linear response. Finally, always within linear response, it is allowed to have Carnot efficiency and nonzero power simultaneously .
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