Time-Domain Standing-Wave Approach Based on Cold Cavity Modes for Simulation of DFB Lasers

A standing-wave model based on “cold” cavity mode expansion is proposed and presented for simulation of distributed feedback (DFB) semiconductor lasers. The model is validated against the well-established traveling-wave model in terms of the static and dynamic characteristics of typical DFB lasers. Effects such as the longitudinal variation of carrier and photon densities and nonlinear gain saturation, known as the spatial and spectral hole burning, respectively, are all included in this model. Simulation examples show that the proposed approach is computationally more efficient than the traveling-wave model. The impact of the expansion mode truncation on the accuracy and efficiency is also investigated and discussed.