Molecular beam epitaxy growth of quantum dot lasers emitting around 1.5 μm on InP(3 1 1)B substrates

We present a modified growth procedure used to control the emission wavelength of InAs quantum dots in a GaInAsP matrix grown on InP(3 1 1)B substrates by gas source molecular beam epitaxy. In this procedure, the quantum dots are grown on a GaInAsP buffer layer and partially capped with the same GaInAsp alloy. Then As/P exchanges during a growth interruption are used in order to reduce quantum dots height and thus to control the emission wavelength. Two GaInAsP quaternary alloys composition have been studied in this work. Both could be used as optical waveguide in 1.55 μm laser diodes. We present and compare photoluminescence results on test structures with these two quaternary alloys. Finally, the new growth procedure is successfully applied and we demonstrate a quantum dot laser emission at 1.58-1.61 μm at 300 K.