Design of high power pump lasers for C-band EDFA amplifiers

High performance fibre EDFA amplifiers for dense WDM systems require efficient and economic pumping devices. One way of providing high pumping power to an EDFA amplifier at low cost is to use tapered semiconductor lasers. The development of a software package for the design and optimisation of these high power tapered laser diodes is described. Cold cavity modelling enables the influence of the laser geometry on the overall performance of the cavity to be investigated along with the beam spoiler design. A 2.5D hot cavity laser model also takes into account effects such as spatial hole burning, carrier diffusion and current spreading. This enables detailed investigation of the laser design and the factors limiting beam quality to be carried out. Our present research aims to incorporate a 3D model of the optical propagation into the laser model using wide-angle FD-BPM schemes, novel finite difference techniques, and modem matrix solvers to minimize memory usage and calculation time.