Journal of High Energy Physics

, 2018:174 | Cite as

Scalar and fermionic Unruh Otto engines

  • Finnian Gray
  • Robert B. Mann
Open Access
Regular Article - Theoretical Physics


We investigate the behaviour of quantum heat engines, in which a qubit is put through the quantum equivalent of the Otto cycle and the heat reservoirs are due to the Unruh effect. The qubit is described by an Unruh-DeWitt detector model coupled quadratically to a scalar field and alternately to a fermion field. In the cycle, the qubit undergoes two stages of differing constant acceleration corresponding to thermal contact with a hot and cold reservoir. Explicit conditions are derived on the accelerations required for this cycle to have positive work output. By analytically calculating the detector response functions, we show that the dimensionality of the quadratic and fermionic coupling constants introduces qualitatively different behaviour of the work output from this cycle as compared to the case in which the qubit linearly couples to a scalar field.


Black Holes Thermal Field Theory 


Open Access

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Copyright information

© The Author(s) 2018

Authors and Affiliations

  1. 1.Perimeter InstituteWaterlooCanada
  2. 2.Department of Physics and AstronomyUniversity of WaterlooWaterlooCanada

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