Fabrication And Property Research Of Multicomponent Tellurite Glasses

As a new kind of glass material, tellurite glasses have become one of the hottestresearch topics these days. Tellurite glass has the following advantages including awide transmission window of0.35⁶μm, low phonon energy (≤800cm^-1), highrefractive index （n=1.8².3）, high nonlinear refractive index (n2=².5×10^-19m²/w),large stimulation emission cross section and gain bandwidth over80nm. In addition,tellurite glass can be easily made into various shapes thanks to its physical andchemical stability and resistance to water corrosion.In this dissertation, we focused on the development of visible laser materials,mid-infrared （mid-IR） window material, and high nonlinear material for all opticalswitching.The main research contents of this dissertation are shown as follows:1) Tellurite glasses for visible fiber laser development. Without devitrificationphenomenon, a few wt%of Yb³⁺and Tb³⁺ions were doped into tellurite glasses.Even by naked eyes, intense green fluorescence was observed. Tellurite glass witha composition of80TeO₂–10ZnO–10Na₂O （mol%）+1.0wt%Tb₂O₃+3.0wt%Yb₂O₃was found to present the highest green light intensity. The mechanism ofthe fluorescence and the profits of tellurite glass to develop visible laser wereanalyzed in detail.2) Water-free fluorotellurite glasses for mid-IR window. Water-free fluorotelluriteglasses were successfully fabricated by “physical&chemical dehydrationtechnique.” Taking5mm-thick water-free tellurite glass as an example, its⁸0%transmitting window covers ultraviolet-visible wavelength to mid-infraredwavelength, meeting the need of the atmospheric transmission window at therange of0.3⁵μm.3) Noble-metal nanocrystals incorporated tellurite glasses for nonlinear applications. To develop high nonlinear optical fibers for all-optical switchingapplications,7.5wt%AgNO₃were incorporated into a typical tellurite glass withcomposition of75TeO₂-20ZnO-5Na₂CO₃（mol%, TZN75）. SPR absorption peakof Ag nanocrystals embedded in7.5Ag-TZN75glass was found to center at552nm. The experimental results revealed that Ag nanocrystals can remarkablyenhance the non-resonant nonlinearity of tellurite glasses. The non-resonantnonlinear refractive index, n₂, of7.5Ag-TZN75glass was measured to be7.5410^-19m²W^-1at1500nm, about3times of the reference TZN75glass withoutany dopant and27times of the silicate glasses and fibers.4) Main results of the exploration and remaining problems worth for furtherresearches are summarized plus with some advice on improving the materials.