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对掺有镉、硒、硫的玻璃在 6 5 0— 80 0℃退火 4h ,生长了不同尺寸的CdS0 1 3Se0 87纳米晶体 ,测量了纳米晶体的吸收光谱、光致发光 (PL)谱和电调制光谱 ,确定了纳米晶体部分电子态的能量 ,讨论了CdSSe纳米晶体的光学性质与其尺寸之间的依赖关系 .随着纳米晶体尺寸的增大 ,对应激子的吸收峰、PL峰及电吸收信号发生红移 ,表现出明显的量子尺寸效应 .小尺寸纳米晶体的电吸收表现为量子受限的Stark效应 ,而大尺寸纳米晶体的电吸收线形与体材料的相似 ;随着纳米晶体尺寸的增大 ,电吸收信号增强 .所有尺寸的纳米晶体都表现出三阶非线性
The CdS0 1 3Se0 87 nanocrystals with different sizes were prepared by annealing the glass doped with cadmium, selenium and sulfur at 650-600 ℃ for 4h. The absorption spectra, photoluminescence (PL) spectra and electric spectra of nanocrystals were measured. The energy spectra of the nanocrystals were determined and the dependence of the optical properties on the size of CdSSe nanocrystals was discussed.With the increase of size of the nanocrystals, the absorption peak of the exciton, the PL peak and the electric absorption The red shift of the signal shows obvious quantum size effect.The small size nanocrystals show the Stark effect of quantum confinement while the large size nanocrystals have the similar shape of bulk material with the same absorption curve. Increases, and the electrical absorption signal is enhanced. All sizes of nanocrystals exhibit third-order nonlinearity