Research Of Spectroscopic And Gain Characteristics Of Er～(3+) Doped Glass Amplifiers For Optical Communication

The 21^st century is the century of optical net, in order to satisfy different requirements for the characteristics of EDFAs in optical communication, the research on new Er³⁺ doped materials for amplifiers becomes one of hotspots in the field of optical communication. There are mainly three aspects of work in this dissertation:Firstly, a series of new glasses, which include Er³⁺/Yb³⁺ co-doped nibium-phosphate glasses (NbP:EY), Er³⁺/Yb³⁺ co-doped lead-nibium phosphate glass (PbNbP:EY), Er³⁺/Yb³⁺ co-doped tantalum-phosphate glass (TaP:EY) and Er³⁺ doped tungsten-tellurite glass (WTe:Er), are prepared.Secondly, the characteristics of spectroscopic and gain-band of the glasses are analyzed by McCumber and Judd-Ofelt theory. The result shows that, compared with the traditional phosphate glasses, aluminium-phosphate glasses and silicate glasses, the peak value of emission cross section and full width at half maximum of the NbP:EY and TaP:EY glasses are larger, are 6.94 × 10^-21cm², 50nm and 6.88 × 10^-21cm², 52nm, respectively. Energy life of ⁴I_13/2 of Er³⁺ in PbNbP:EY glass is higher, and is 9.11ms. It is helpful for decreasing the pumping threshold power of EDFA. The thermal stability of glasses is researched by the difference thermal analysis (DTA). The result shows the softening points of three types of phosphate glasses are 560℃, 559℃ and 633℃, respectively, which are 250-300℃ higher than those of conventional phosphate glasses. It indicates that the new types of phosphate glasses possess of fine thermal stability, and overcome the hardness in producing waveguide by ion exchange technique, meanwhile. Comparing with the traditional tellurite glasses, the peak value of emission cross section and full width at half maximum of WTe:Er glass are increased greatly and are 9.5×10^-21cm² and 86nm, respectively, and upconversion fluorescence is also minished greatly. Additionally, DTA shows the improvement in thermal stability in WTe:Er glass.Finally, the gain characteristics of NbP:EY and WTe:Er fiber amplifiers are simulated. For NbP:EY glass fiber amplifier, the peak gain at 1536nm is up to 34dB and gain per unit length is about 4dB/cm when the pumping power is 200mW and input power is -30dBm. It shows NbP:EY glass is the desirable gain material for short length...