Theoretical luminescence spectra in p-type quantum wells and superlattices based on InGaAsN

Full text: In the past few years, the dilute nitride system, InGaAsN, is proposed as a good candidate for several device applications. InGaAsN is considered a promising material for laser devices working at 1:3 or 1:5μm and high-efficiency multijunction solar cells. Incorporation of In and N into GaAs result in a strong redshift of the emission wavelength. Besides, the strain can be minimized since the opposite effect of In and N on the lattice constant enables lattice matching of InGaAsN on GaAs. However, despite their great potential for applications, the understanding of their physical properties is rather incomplete. In particular, the dominant mechanisms of light emission in these alloys and their dependence on the nitrogen composition are not well established. Such information is crucial not only for a better understanding of the optical properties of the nitrogen containing III-V alloys, but also for a better technological control of alloy formation and optimization light emission efficiency. Another point concerns to investigation in p-type doping in InGaAsN. This is of great importance since, for example, can improve the transport in HBT (Heterojunction Bipolar Transistors) devices. In this work we report on theoretical luminescence spectra calculations for p-doped GaAs/InGaAsN quantum wells and superlattices. The calculations are performed within the k-vector.p-vector method by solving the full 8 x 8 Kane Hamiltonian, generalized to treat different materials. Strain effects due the lattice mismatch between InGaAsN and GaAs are taken into account. By varying the acceptor concentration we analyze the effect of exchange-correlation, which plays an important role in profile potential and electronic transition. These results can explain several important aspects about optical properties in these systems. (author)