Numerical analysis of concentration quenching model of Er/sup 3+/-doped phosphate fiber amplifier

Based on the homogenous model and inhomogeneous model of concentration quenching of erbium-doped fiber amplifier with high doping concentration, the rate equation and power evolution equation of erbium-doped phosphate fiber are solved numerically and analyzed. The dependence of the calculated gain and noise figure on pump power is compared with experimental data, and the results indicate that the combined model of the two models is in good agreement with experimental data. The relative number of clusters in erbium-doped phosphate fibers is estimated from the numerical analysis, and the optimal doping concentration and length of erbium-doped phosphate fibers are proposed in this paper. By numerical analysis, the results show that with 200-mW/980-nm pump power, an erbium-doped phosphate fiber amplifier with a doping concentration of 4.0*10/sup 26/ ion/m/sup 3/ and length of 10 cm may reach 27.0-dB gain.