Numerical analysis of amplification characteristic of erbium-doped waveguide amplifiers by FD-BPM

An efficient analysis method for erbium-doped optical waveguide amplifiers (EDWA) is presented. By solving the rate equation, the propagation in EDWA is stimulated using the finite difference beam propagation method (FD-BPM). The dependence of the gain of EDWA is investigated on the waveguide length, erbium concentration, and signal and pump power. The analysis shows that considerable gain levels, 3.35 dB/cm can be achieved in 10 cm-long EDWA with an erbium concentration of 2.0 × 10²⁶ ions/m³, signal power 1 W and pump power 100 mW at 980 nm.