Optimum pumping scheme of dual-stage triple-pass erbium-doped fiber amplifier

The optimization of pump power for a new configuration of dual-stage triple-pass Erbium-doped fiber amplifier is successfully demonstrated. This configuration incorporates two-stage amplifiers with two independent 980-nm pump lasers. The first-stage amplifier consists of double-pass amplification to obtain high gains and the second-stage amplifier is single-pass amplification in backward pumping schemes. The maximum gain that obtained in the experiment does not have the minimum noise figure. Therefore, the optimum operating point is defined based on the ratio of gain to noise figure. The relationship between the pump-power distributions in the proposed configuration shows that the optimum pump ratio of the first-stage pump laser to the total pump power is around 0.3 to 0.5 depending on the signal powers.