Photoexcited carrier lifetime and Auger recombination in 1.3-μm InGaAsP

Abstract

We have measured the time-resolved decay of photoexcited carriers in InGaAsP subsequent to mode-locked laser pulse excitation at 1.06 μ. Carrier decay rates were evaluated from bleaching recovery and luminescence decay measurements as a function of injected carrier density over a two-decade range (1017–1019 cm−3). At low and moderate density the decay rate follows the variation with excitation expected for radiative decay. At high carrier density (above 2×1018 cm−3), the decay rate increases more rapidly with carrier density, indicating the onset of nonradiative recombination which can be accounted for by Auger recombination with an Auger coefficient of A=2.3±1×10−29 cm6 s−1. This compares to the calculated Auger coefficient range of 0.7–1.4×10−28 cm6 s−1. We discuss the influence of our measured decay rates on the threshold temperature dependence of InGaAsP-1.3 μ lasers by calculating expected T0 values, using a range of representative values for threshold carrier density and temperature dependence of the Auger decay rate. Our results suggest that while Auger recombination does contribute to the temperture dependence of the InGaAsP-1.3 μ laser it may not alone fully account for the observed room- temperature T0 values.