The reverse flow and amplification of heat in a quantum-dot system

We demonstrate that when a quantum dot is embedded between the two reservoirs described by different statistical distribution functions, the reverse flow and amplification of heat can be realized by regulating the energy levels of the quantum dot and the chemical potentials of two reservoirs. The reverse heat flow and amplification coefficient of the quantum device are calculated. The novelty of this device is that the reverse flow of heat does not need externally driving force and this seemingly paradoxical phenomenon does not violate the laws of thermodynamics. It is further expounded that the quantum device has some practical applications. For example, the device can work as a micro/nano cooler. Moreover, the performance characteristics of the cooler are revealed for different distribution functions. The coefficients of performance of the cooler operated at different conditions are calculated and the optimum selection criteria of key parameters are supplied.