热处理温度对量子点玻璃介电函数的影响

Influence of Annealing Temperature on the Dielectric Function of Quantum Dots Doped Glass

为了明确热处理温度对熔融法制备Pb Se量子点玻璃光电特性中介电函数的影响,实验上在不同核化时间、晶化温度条件下制备了多种样品。通过对样品透射电子显微镜的观测,确认样品在不同条件下都有一定量的晶体形成。由于晶化程度、晶体大小及浓度有所不同,导致其吸收光谱有一定差异。利用各个样品的吸收光谱,结合米氏散射理论和克拉默斯-克勒尼希关系,通过多次迭代运算,从吸收光谱中分离出相应的介电函数的实部和虚部,最终获得材料的吸收系数和折射率。分析表明退火温度对量子点玻璃的吸收系数和折射率分布有明显的影响,为了获得具有优良光电性能的量子点材料,退火时间和退火温度的合适选择至关重要。

In order to reveal the influence of annealing temperature on the photoelectric characteristic of Pb Se quantum dots doped glass produced by a melt-annealing technique, experiments are carried out to compare the influence of different nucleation time and crystallization temperature. The transmission electron microscope images show that a certain amount of Pb Se crystals are crystallized in the glass. While the degrees of crystallization, particle size and density have some slightly difference. A procedure combined the Mie scatter theory and the Kramers-Kr？nig relation is used to calculate the real and imaginary parts of the dielectric function from the experimental absorption spectrum. The calculation results indicate that the annealing temperature has obvious influence on the absorption coefficient and the refractive index. So the suitable annealing temperature and duration are the important factors in the preparation process of quantum dots doped glass with excellent photoelectric properties.