利用K-K关系计算量子点玻璃的介电函数

为了得到PbSe量子点(QD)玻璃的光学常数,为 实验制备QD材料提供定性和定量参考,本文利用 实验中测量的吸收光谱,结合米氏散射理论和克拉默斯-克勒尼希(K-K)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,最终获得材料的光学常数。为了使矩阵迭代运算 能够快速收敛, 设计了一种快速、不产生奇异矩阵的简便方法。计算得给出的PbSe QD玻璃的介电函数与 实验测量得到 的胶体QD介电函数分布非常相似,表明本文方法能够用于快速测定QD玻璃的介电 函数。本文方法可 以推广到其他液体、固体和气体材料光学常数的测量中,为纳米材料制备提供一定的参考。

Dielectric function of quantum dots doped glasses obtained by K-K relation analysis

In order to obtain the optical coefficient of quantum dots doped glasses and pro vide qualitative and quantitative analysis in the preparation process of quantum d ots,a procedure combining the G.Mie scatter theory and the Kramers-Krnig relations is used to calculate the rea l and imagi nary parts of the dielectric function from the experimental absorption spectrum by iterative method.A simple and quic k method is developed to avoid the singular matrix in the process of matrix iterative approach.The calcu lated results of the dielectric function of PbSe quantum dots doped glasses are very similar to the experimental results of colloidal PbSe quantum dots.This method can conveniently get the dielectric coefficients of many types of materials,such as liquid,solid and gas materials.It can be a good reference for the manufacture of other nano m aterials.