Study On The Optical Properties Of Rare Earth Doped Sol-gel Glasses

Sol-gel glass possesses attractive advantages including homogeneous structure, controllable composition and easy fabrication, which is considered to be a promising type of optical material. This glass material has broad applications in the fields of optical sensor, luminescent device, solar cell and so on. However, due to the compolicate structure of non-crystalline solids, it is still lacking in our knowledge of structure-property relations of glass, which is fairly important for the future development of glass science and technology. In this thesis, we focusd on several typical glass properties, including UV-shielding property, luminescence property and whisper galley mode (WGM) resonance property. We tried to improve the performance of glass by rational micro-structure engineering. On whole, this thesis includes three research topics:(1) To enhance the UV-shielding property of Ce-doped silicate glass, we introduced an effective self-limited nanocrystallization approach for in situ construction of composite UV absorber derived from Ce-containing glass. We found that the amorphous-crystalline change and ratioanl doping can be simultaneously realized in glass. The obtained UV-shielding glass presents low activity and high optical transparency. Finally, we demonstrated that the obtained robust UV absorber can effectively protect organic dye and living cells against UV irradiation damage.(2) For the Er/Ce codoped silicate glass ceramic, we found an interesting phenomenon that the NIR luminescence can be greatly enahanced with the increase of heat-treatment temperature. We further investigated the physical mechanism:it should be associated with the effective removal of emission quenching center -OH group from glass, which was mainly contributed by the nanocrystallzation of CeF3 and the followed oxidation of nanocrystals. The proposed way for removing harmful-OH group was considered to be an useful pathway for enhancing the photoluminescence property of sol-gel glass.(3) We introduced a scalable approach, based upon non-hydrolytic sol-gel (NHSG) process, for deposition of Yb/Er co-doped tellurite glass film with high homogeneity. This pathway would circumvent some sticky issues of hydrolytic sol-gel process, such as the dismatch between hydrolysis and condensation rate. The structure and photoluminescence property of the fabricated glass were investigated. The reliable thick film was further fabricated into microcavity on silicon and the whisper galley mode (WGM) resonance property was demonstrateed. To the best of our knowledge, the progress provides the first prototype of chip-based optical microcavity derived from multi-component glass.