J. Tittel et al., INVESTIGATIONS OF THE EMISSION PROPERTIES OF SINGLE CDS-NANOCRYSTALLITES, Berichte der Bunsengesellschaft fur Physikalische Chemie, 101(11), 1997, pp. 1626-1630
Citations number
23
Categorie Soggetti
Chemistry Physical
Journal title
Berichte der Bunsengesellschaft fur Physikalische Chemie
Semiconductor nanocrystallites (NCs) with a radius in the range of the
bulk exciton radius exhibit a strong quantum size effect. We investig
ated CdS-NCs, that were spin coated on a glass cover slip, with a low
temperature confocal microscope. At low coverage we could image the fl
uorescence light from single NCs. The typical emission spectra of sing
le NCs show four peaks. Besides the main peak related to near bandgap
recombination, up to two LO-phonon satellites and one blue shifted pea
k were observed. It could be shown that the absorption can be polariza
tion dependent. From the images as well as from the intensity autocorr
elation function it could be concluded that the fluorescence emission
of single NCs is interrupted by dark periods. In addition, spectral sh
ifts in the dispersed fluorescence emission could be observed.