Dominance of auger recombination in InGaAsP light emitting diode current-power characteristics

Output power saturation in 1.3-µm InGaAsP light emitting diodes with various active layer thickness has been investigated experimentally in a wide temperature range. Nonradiative recombination current with strong injected carrier density dependence, which is responsible for saturation, was found to be proportional to active layer thickness and almost independent of temperature under constant injected carrier density conditions. External quantum efficiency at a constant injected carrier density was found to be independent of active layer thickness. These results indicate strongly that Auger recombination is the dominant nonradiative process in InGaAsP light sources.