Sol - Gel Prepared Erbium Doped Waveguide Amplifier

EDWAs(Erbium Doped Waveguide Amplifiers) are basic optical components in future fiber-optic communication systems,especially in local area networks and metropolitan area networks.Among several fabricating techniques applied to the EDWAs,sol-gel method attracted more and more attentions in the past few years, because of its simple process,low cost,moderate annealing temperature,high homogeneity and good dispersion of dopants.This thesis reports our research works on the Silica-on-Silicon EDWAs fabricated by the sol-gel method and wet etching process.The main results of the thesis are as follows:Ⅰ.The silica films,which were doped with 0.5%Er³⁺,0.5%Yb³⁺,10%P₂O₅, 5%Al₂O₃(mol%),were deposited by the sol-gel method.The refractive indices of the films were 1.466～1.468 and the thickness were about 5～6μm,with the surface roughness of 0.139nm.The 1.55μm photoluminescence(PL) lifetimes of the sample indicated a fluorescence quantum efficiency of 30%.These results ensured that the EDWAs could be achieved based on the sol-gel technology.Ⅱ.A novel waveguide structure was designed.To illustrate the details,the BeamPROP Program was applied to simulate the propagating modes of both the signal light and the pump light,their individual energy distribution in the guiding layer,the cladding layer and the Erbium doped buffer layer were calculated as well.Ⅲ.The EDWAs were achieved with the wet etching process.The detailed processes were investigated and the optical properties of the EDWAs were measured. The results showed that the propagation loss at 1310nm was 0.93dB/cm,the coupling loss was 8.82dB,and the maximum relative gain of 5dB was achieved under the dual-150mW pump condition.At the optimal EDWA length,which was about 3.3cm, the maximum average gain obtained was 1.5dB/cm.