Optical and electronic properties of AlInGaN/InGaN superlattices

In this work we analyze the theoretical photoluminescence (PL) spectra from strained AlGaInN/InGaN and InGaN/AlGaInN superlattices (SLs). The calculations are performed within the k.p framework by means of the solution of the 8!8 effective mass Kane Hamiltonian generalized to treat layers of different materials. Strain effects due to lattice mismatch and the split-off-hole band were also taken into account. The results indicate that PL emissions observed in these systems are due to recombination from confined states inside the quantum well. In both cases, considering the quaternary nitride alloys in the barrier and in the well, we have feasibility of light emissions sweeping the visible region spectra from blue through red. This is the first attempt to show theoretical luminescence spectra for cubic AlInGaN/InGaN SLs and can be used as a guide for the design of white light emission diodes (LEDs) and other devices. q 2005 Elsevier Ltd. All rights reserved. PACS: 73.20.Dx; 71.15.-m