Inter- and Intraband Transitions in Cubic Nitride Quantum Wells

In this work we analyze the luminescence emissions from selected isolated GaN/InGaN quantum wells comparing measured and theoretical photoluminescence (PL) spectra. The calculations are performed within the k . p method by means of an 8 x 8 Kane Hamiltonian, generalized to treat different materials. Strain effects due to the large lattice mismatch between InN and GaN are taken into account. From the direct comparison with experimental results, we found evidence for transitions involving confined levels which, besides those related to quantum dots, may be ascribed to the first electron-heavy-hole transition in the quantum wells. Since the studies of optical properties of quantum wells based on cubic nitrides are at an early stage, the results reported here will provide guidelines for the interpretation of forthcoming experiments.