Optical characteristics of 1.55μm GaInNAs multiple quantum wells

We report the optical characterization of high-quality $1.55\mu \mathrm{m}$ ${\mathrm{Ga}}_x{\mathrm{In}}_{1-x}{\mathrm{N}}_y{\mathrm{As}}_{1-y}$ multiquantum wells (MQWs), grown on GaAs with $\mathrm{Ga}\left(\mathrm{In}\right){\mathrm{N}}_{0.01}\mathrm{As}$ spacer layers. The transitions between the quantized QW states of the electrons and holes have been identified using photoluminescence excitation spectroscopy. Their energies are consistent with theoretical fitting based on the band anticrossing model. It is also confirmed by detailed spectroscopic measurements that the addition of even a small amount of In to $\mathrm{Ga}{\mathrm{N}}_{0.01}\mathrm{As}$ barriers remarkably improves the optical characteristics of the QWs. The results imply that although strain-compensated GaInNAs MQWs provide a feasible approach to realizing $1.55\mu \mathrm{m}$ optical emission, the relative lattice mismatch between the wells and barriers is critical to the optical quality of the related QWs.