Gain modelling and particle balance in semiconductor lasers

An outline is given for one method of large signal time domain modelling of semiconductor lasers, which preserves photon-electron balance for a wide range of unknown spectral inputs by using a time domain filter in the recombination equation as well as in the field excitation equations. The gain filter has an approximately parabolic gain profile in the frequency domain, and can be implemented at each point of the laser and have its peak gain, frequency of peak gain and gain bandwidth change as the electron density changes. Some preliminary differences are examined using a recombination equation gain filter (REGF) or no REGF for large signal, time domain models of a laser amplifier and a phase shifted DFB