The Research On Carrier Transport Mechanism Of Thermal Electrical Cooler

Since the 1960 s,Thermal electrical cooler began to be widely studied,because thermal electrical cooler has many excellent potential advantages.At present adoption of the body structure materials of thermal electrical cooler has been applied in many fields. In the new century,with the further development of nanometer science and technology,more and more new materials and components of thermal electrical cooler are developed.Combining with the computer simulation method and experimental test,we study the related problems of thermal electrical cooler.First of all,The research status and development bottleneck of thermoelectric cooling are summed up and summarized in this paper,and a new type of thermoelectric cooling method are introduced,and the coefficient of merit ZT of the key of thermoelectric cooling has carried on the related mathematical derivation.Using mathematical calculation software, a simulation model is established based on the theory of lattice dynamics.Through the research on the phonon spectrum and phonon density of states of semiconductor superlattice materials,I found that for the density of states,when atomic layer increased, the trough and peak number increased at the same time,and peaks and valleys correspond to van hove singularities, moving in the direction of the high frequency, this phenomenon has a very close relationship with the effects of the center and zone boundary of the brillouin zone.From the phonon spectra we can conclude that with increasing atomic number of layers, the lattice vibration mode also increases.When the semiconductor superlattice is the structure of ? ??nnn????? 5,4,3,2?, altogether there are 2n degeneracy, which includes n optical branching degeneracy and n acoustic branch degeneracy.Second,refer to typical thermal electrical cooler,combined with electroluminescent cooling, a new type of semiconductor refrigerating unit was developed.I found that as long as the electroluminescent devices of optical output power is greater than the electrical input power, the refrigeration can be realized.And then survey and study the basic principle, materials and structure of of the electroluminescent device,and generate the electroluminescent refrigeration components through using liquid phase epitaxy(LPE) growth techniques,and the specific growth process is presented.Finally,setting up the experimental test platform based on the experiment scheme,through the experiment test of electronic light-emitting device I found that when the voltage kqTVB?/ in the low bias mechanism, the external quantum efficiency EQE? is independent of the voltage,so that further reduce voltage can increase the energy conversion efficiency ?,and by moving the narrow band gap materials and improve emitter lattice temperature,available power can increase a few orders of magnitude in the low bias mechanism.When the current is small, the current and the external quantum efficiency are independent of each other, a little deviation of the thermodynamic equilibrium and the generation of net photons can be implemented by voltage qTV kB??/. In the low bias mechanism,the external quantum efficiency also increases with the increase of temperature, energy conversion efficiency is inversely proportional to the optical output power,external quantum efficiency has a linear relation with independent voltage and current voltage characteristic, energy conversion efficiency of electroluminescent is over 100%,net cooling can be realized.The feasibility of the experiment scheme is verified.