  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.
