The Optical Characterzation Of Ⅱ-Ⅵ Nano Semiconductor

The optical characteristic of ZnO, CdSe nano semiconductor have been studied in this thesis, including their absorbing and fluorescent properties, and the influence of substrate temperature and adulteration of Manganese and Silver to these properties. Our study theoretically analyzed the appearance and character of polarized fluorescent spectrum and the appearance of random laser. The intention of this thesis is to thoroughly study the optical character of nano materials, theorize the model of optical energy transferring in nanocrystal, and to provide the experimental and theoretical basis for application of nano-materials. The main contents of the thesis is as following:1. We analyzed the optical character of ZnO nanocrystal, including the influence of particle size and substrate temperature to its optical character and energy gap and proved that substrate temperature will greatly influence the optical character and maximum gain. We also studied the temperature dependent excited luminescence. We observed the relationship between the adulteration ZnO nanocrystal with Ag, Mn and the consequent change of optical property of these compounds. We analyzed the influence of topologized structure to absorbing character, and set up a fully binding-up model based on our experience, demonstrated by ZnS nanocrystal absorbing spectrum data.2. According to phenomena of random laser in random system composed of ZnO powder, we studied the principle of random laser in semiconductor powder, including its optical character and the influence of the environmental parameter to random laser property. And also we presented the time reliant theory in random laser system and demonstrated it.3. The optical character of CdSe nanocrystal, including the preparation, token, absorbance and fluorescence property were finely studied, especially the size selective fluorescence character and the variety rule of dielectric constant in QD.4. We studied the principle of polarized luminance; setup a method to determine polarized angle of luminance. Our results suggested that the research of polarizedluminance will benefit the study of excited and exciting energy level, transition probability, and delay mechanism in nano semiconductor.