Pseudopotential Theory of Electronic Excitations in Semiconductor Nanostructures

The calculation of the optical and electronic properties of semiconductor nanostructures is still based for the most part on highly approximated, continuum-like models such as the effective-mass approximation, which do not take into account the atomistic structure of the quantum dots. We present here an atomistic pseudopotential approach to the calculation of excited states in semiconductor nanostructures. This approach involves two steps: (i) The single-particle Schrödinger equation for the nanostructure is solved using O(N) methods. (ii) The electronic excited states (such as excitons, multi-excitons, etc.) are then calculated by solving the many-particle Schrödinger equation in a basis set of Slater determinants (configuration interaction epansion). Applications of this method to predict the optical emission spectra of neutral and charged excitons, bi-excitons and tri-excitons in CdSe colloidal quantum dots are discussed.