Effect of scattering on the longitudinal mode spectrum of 1.3 μm InGaAsP semiconductor diode lasers

The scattering of stimulated emission within InGaAsP semiconductor diode lasers has been measured and correlated with the measured spectral output of the lasers. It is found that the spectral output of the diode lasers is strongly dependent on internal scattering. It is also found that the amount of scattering is characteristic of the laser structure. A theoretical model has been developed which demonstrates the effect of scattering on the spectral output, and which explains the differences observed in the spectral output of different structures in terms of the internal scattering.