Ultralow recombination velocity at Ga0.5In0.5P/GaAs heterointerfaces

Abstract

Using time‐resolved photoluminescence, we have examined the optoelectronic properties of Ga_0.5In_0.5P/GaAs/Ga_0.5In_0.5P double heterostructures grown by organometallic chemical vapor deposition. For comparison, similar structures using Al_0.4Ga_0.6As/GaAs and Al_0.5In_0.5P/GaAs lattice‐matched heterointerfaces were also examined. For the Ga_0.5In_0.5P/GaAs heterostructure, we show that the recombination velocity at a Ga_0.5In_0.5P/GaAs interface can be less than 1.5 cm/s. As a result, photoluminescence decay times as long as 14 μs have been observed in undoped GaAs double heterostructures. This photoluminescence decay time varies with temperature as T^1.59, characteristic of radiative recombination not limited by surface or bulk nonradiative recombination processes. For the Al_0.4Ga_0.6As/GaAs and Al_0.5In_0.5P/GaAs heterostructures examined in this study, the upper limits of the interface recombination velocity were 210 and 900 cm/s, respectively.