Optical properties of quantum wires and dots

Abstract

Recent work on the optical properties of quantum wire and quantum dot systems is discussed, including carrier, phonon and photon states, electronphonon scattering and excitonic effects. In realistic systems the geometry often results in the equations for the elementary excitations being non-separable. Numerical methods for calculating these excitations are discussed with emphasis on “boundary element methods”, which we have recently developed. Electron-LO phonon scattering rates in quantum wires are given based on single particle results for electrons and phonons. Electron- acoustic phonon scattering rates in quantum dots including the effects of coupling to the dot surroundings and of a novel acoustic phonon scattering mechanism are discussed. For the optical transition energies comparisons are made with recent experimental results on a series of lithographically formed quantum wire and quantum dot structures, including deep etched and modulated barrier structures with and without magnetic fields. Exciton binding energies in these structures are calculated variationally and are found to depend on confinement and to be in agreement with experiment.