Thermionic and tunneling cooling thermodynamics

The entropy fluxes and irreversibilities of the quantum and classical processes that limit the performance of thermionic and tunneling chillers were analyzed. It was shown that the entropy flux stems from electron emission, electron flow in the external conductor. It was found that the emitted electrons extract thermal energy from electrodes and return an identical energy to them as they return to fermi levels. The quantitative illustrations allowed to trace thermodynamic trajectories through cooling cycles, and unified the thermodynamic perspective of the quantum chillers with conventional cooling cycles.