| In recent years,a new technology,photon-enhanced thermionic emission,is pro-posed,which can effectively combine the "quantum" and "thermal" approaches into a single process.Nevertheless,the relevant researches were in its infancy and remain in the theoretical study level with little experiment.This paper studied the design and prepa-ration of Ga1-xAlxAs/GaAs PETE device?the efficiency model and the temperature dependence of photoemission characteristic based on the basic structure and theoretical model of PETE device.Firstly,the Gal-xAlxAs/GaAs materials were modified and grown by MOCVD tech-nology.Moreover,the cathode components were prepared with chemical cleaning and Cs/O activation.Then,the device can be obtained by the indium seal technology with the help of Key laboratory of light.Secondly,in this paper,a Ga1-xAlxAs/GaAs cathode was proposed to be applied on PETE device.The theoretical model with this complex photocathode is deduced based on one-dimensional continuity equations to analyze the characteristics of the device.The results demonstrated that the multilevel built-in electric fields can effectively boost the transport of photoelectron,then improve the performance of device.Finally,the temperature dependence of photoemission characteristics,which was from AlxGa1-xAs/GaAs cathode was studied with related equipments.The effect of temperature on energy distribution and photoemission yield was experimentally stud-ied in the wavelength range 450-850 nm.The variation of the energy distribution and photoemission yield with increasing temperatures demonstrates that direct photoemis-sion gradually declines,while PETE contribution increases with increased heat.The given results showed that the Ga1-xAlxAs/GaAs cathode can be an ideal candidate for high-performance PETE device.The researches in this work is an innovation exploration of photoelectric conversion,which is crucial to the future utilization of solar energy. |
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