Scalar and fermionic Unruh Otto engines

Understand

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.