| Quantum Confinement Effects of Semiconductor Nanocrystals CdSaiSeo9in GlassAbstractA series of CdS0.iSeo.9 semiconductor nanocrystals embedded in silicate glass with different sizes have been fabricated by one-step and two-step annealing methods .The electronic state and optical properties of these nanocrystals also have been studied through room-temperature absorption spectra and electroabsorption spectra .It has shown that two-step procedure could increase the number of nanocrystals,but improve the size distribution only in a minor way ..The size of nanocrystals was controlled by heating time .From absorption spectra and the second-order derivative spectra , three absorption speaks of excitons were clearly resolved . At the same time, the first exciton absorption peak got stronger with decreasing nanocrystals size. Blue shifts due to quantum confinement were observed obviously. The shifts of absorption edge of nanocrystsls compared with that of bulk have been calculated by means of effect-mass approximation model. The calculation and experimental results looked almost same .CdSo.iSeo.9 nanocrystals exhibited the excellent resonant and non-resonant third-order optical nonlinearties from electroabsorption spectra. Quantum size effect was also observed.
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