Published online by Cambridge University Press: 17 March 2011
Quantum confinement and photoluminescence properties of self-assembled InAs quantum dot arrays on GaAs substrates are studied theoretically using a coupled morphology/electronic structure finite element approach. Simulations of island evolution due to strain energy driven diffusive mass transport are first used to generate realistic island arrays. The resulting finite element meshes are input to a continuum, single charge-carrier model in which band structure properties are prescribed using a k•p Hamiltonian formulation. The results of the electronic properties analysis are spectra of electron and hole energies and corresponding wave functions. The electron and hole states have characteristics unique to arrays, the most prominent of which are the energy separations due to size and shape variations among dots in the array. This feature is shown to lead directly to inhomogeneous broadening in the photoemission spectra. Other phenomena observed here include the onset of a discrete density of states at the point of island formation during growth; the presence of states with wave functions coupling multiple dots in the array; and the nature of wetting layer states in the system.