Study on the Upper State Population Distribution of Double Cladding Erbium-ytterbium Co-doped Fiber Amplifiers
双包层Er-Yb共掺光纤放大器上能级粒子数分布研究

Based on rate and power propagation equations, the upper state population distribution of Er 3+ and Yb 3+ of an double cladding erbium-ytterbium co-doped fiber amplifier was analyzed numerically under three different 972 nm pumping scheme. It was shown that the upper state population distribution of Er 3+ is chiefly affected by signal power and its lasing rate is almost kept upward of 50%; and that the upper state population distribution of Yb 3+ is chiefly affected by pump power and its lasing rate is almost kept under 10%. The results could be important for the characteristic investigation of double cladding erbium-ytterbium co-doped fiber amplifiers.