Erbium-doped phosphate fiber amplifiers

In this paper, the development of phosphate glass fiber amplifier with a high gain per unit length is reviewed. The performance of compact multimode pumped erbium-doped phosphate fiber amplifiers is presented. A fiber amplifier with a small signal net gain of 41dB at 1535nm and 21dB over the full C-band was demonstrated using a newly developed 8-cm long erbium-doped phosphate fiber excited with a 1-W, 975-nm multimode laser diode. A theoretical model was developed for the multi-mode pumped amplifier based on modified rate equations and effective beam propagation method. Close agreement between experimental and modeling results is observed.