Correlation between experiments to measure scattering centers in 1.3 μm semiconductor diode lasers

Data obtained from two techniques on light scattering centers that are distributed along the length of the active region of 1.3-μm InGaAsP/InP diode lasers are presented and discussed. Light scattering characteristics were obtained for 16 lasers by analyzing light detected through the substrate (using spatially and polarization resolved electroluminescence) and by analyzing the facet emission for modulation features in the below-threshold reflectance-gain (R_m G_m) product. A Cartesian plot of the data shows the points to be dispersed about a best-fit line, but correlated. The failure to fall within experimental uncertainty on a line can be explained by a sampling phenomenon due to the discrete nature of the longitudinal modes and by the assumption of unequal or anisotropic scattering in the substrate and facet directions. The data are taken to show that the scattering is not isotropic