Performance analysis of an interacting quantum dot heat engine with an external applied magnetic field

• A general model of the quantum dot heat engine is proposed.
• The effects of Coulomb and magnetic fields are considered.
• The maximum power output and efficiency are determined.
• Suitable region of the external applied magnetic field is given.
• Several models adopted recently in literature are unified.

A general model of a single orbital interacting quantum dot embed into two metal leads is established, in which an external applied magnetic field is considered and a linear fade of the Coulomb energy resulting from the energy level splitting is introduced. The occupation probabilities of quantum states are determined by the master equation under the steady state condition. The expressions of matter fluxes, heat fluxes, power output, and efficiency are derived. The effects of both the magnetic field and energy level on the performance are discussed. The maximum power output and efficiency are calculated. The optimal regions of the energy level and magnetic field are determined. Some important conclusions in literature can be directly deduced under the different extreme conditions of the present model.