Simple and accurate procedure for modelling erbium-doped waveguide amplifiers and lasers with high erbium concentration

We present a new, very intuitive and simple approach to model waveguide amplifiers and lasers with high erbium concentrations. The basic approximation used the modelling is anchored on the small contribution of the nonlinear terms to the photon population densities. An assumption which is still valid in present laser and amplifier configurations. The model is tested against several experimental results and is shown to be in a very good agreement. (6 pages)