Abstract
Single-dot spectroscopy was used to determine the temperature dependence of the ground-state exciton energy in self-assembled quantum dots (QDs) from up to . Differences of dot composition and geometry are manifested primarily in the absolute transition energies, whereas the band-gap reduction depends only weakly on microscopic details. can be well described by semiempirical phonon-dispersion models developed recently for bulk, suggesting that thermal lattice expansion and electron-phonon interaction are the dominant mechanisms for , whereas QD-specific mechanisms seem to be of minor importance, in contrast to observations for nanocrystals.
- Received 19 December 2003
DOI:https://doi.org/10.1103/PhysRevB.72.085328
©2005 American Physical Society