Er-yb Co-doped Phosphate Glass Fiber

The domestic and foreign developments of Er/Yb co-doped phosphate glass fiber are briefly introduced in this paper. Then considering the disadvantage of EDFA and YDFA, the following works are accomplished, including fabricating Er/Yb co-doped phosphate glass material, testing each chemic and physical charicteristics of Er/Yb co-doped phosphate glass and designing double clading single mode fiber etc.After introducing gain theory of EDFA and YDFA, the rate equation and propagation equation of Er/Yb co-doped phosphate glass fiber are simplified, and each factors relating to the gain of fiber amplifiers, such as fiber leghth, pumping power, signal power and wavelegth, ion concentration etc. are also described.Each chemic and physical characteristics of phosphate glass is discribed, the compounding and fabrication of Er/Yb co-doped phosphate gain material are argued. Then each characteristics of phosphate glass are presented. The best gain material is also obtained by melting chemic materials in special proportion. And the refractive index is 1.547513, converted temperature is 426°C and Erbium ion concentration is 2.9 g/cm3 through measurement. Furthermore the optic spectrum data of Er/Yb co-doped phosphate glass, such as absorption spectrum, fluorescence lifetime and emission spectrum etc. are also tested.According to each tested data of material and single mode propagation requirement of signal in gain fiber, the core fiber and cladding are designed respectively,and a reasonable double cladding amplifiers fiber structure is showed in this paper. Then after analysising each characteristics of phosphate glass material, the fiber rod-in-tube by invaginating core rod, inside cladding and outside cladding is used to fabricate the Er/Yb phosphate glass fiber successfully by polishing and vacuumizing fiber rod-in-tube.Finally some techniques, such as cladding pump, prism coupling pump and fusing pump are used to measure the gain of fiber amplifiers. And as a best scheme, the fusing...