PHOTOLUMINESCENCE OF SPHERICAL QUANTUM DOTS

In order to interpret the phonon-assisted optical transitions in semic onductor quantum dots, a theory is developed comprising the exciton in teraction with both adiabatic and Jahn-Teller phonons and also the ext ernal nonadiabaticity (pseudo-Jahn-Teller effect). The effects of nona diabaticity of the exciton-phonon system are shown to lead to a signif icant enhancement of phonon-assisted transition probabilities and to m ultiphonon optical spectra that are considerably different from the Fr anck-Condon progression. The calculated relative intensity of the phon on satellites and its temperature dependence compare well with the exp erimental data on the photoluminescence of CdSe quantum dots, both col loidal and embedded in glass.