Exciton‐LO phonon interaction in II–VI self‐assembled quantum dots

Abstract

We study the exciton–LO phonon interaction in CdTe/ZnTe and CdSe/ZnSe self-assembled quantum dots (QDs) by means of resonantly excited PL spectroscopy. We find that in the case of large (∼8–10 nm in diameter) CdSe QDs the strength of the exciton–LO phonon coupling is nearly independent of the dot size (e.g. emission energy). In contrast, for CdTe dots (significantly smaller than the CdSe dots) the exciton–LO phonon coupling increases strongly for QDs with higher emission energy (smaller size). Finally, we show for annealed CdTe QDs that, the exciton–LO phonon interaction again becomes independent of emission energy, consistent with the larger dot sizes created by the annealing. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)