Abstract

Photon-pair correlation measurements on individual CdSe quantum dots coordinated with oligo-phenylene vinylene ligands (CdSe-OPV), generated with 405 nm and 514 nm reveal weak muti-excitonic character in it fluorescence emission as observed by changes in the second order intensity correlation function, g⁽²⁾(0) from 0.22 to 0.05 versus excitation wavelength. Coincidence histogram of CdSe-OPV shows a rise time of ≈ 19 ns similar to ZnS-capped CdSe dot indicating that the presence of the OPV ligands has negligible effect on the radiative decay rate of excitons formed within the dot and point to the mechanistic picture of electron donating species near the dot surface induce fluctuations in non-radiative decay rates that underline the ‘gray level’ intensity flickering in the fluorescence intensity trajectories of CdSe-OPV nanostructures.

© 2009 APS DLS