Environment-dependent blinking of single semiconductor nanocrystals and statistical aging of ensembles

We compare decreasing fluorescence signals from ensembles with the blinking statistics of individual nanocrystals in various environments. For most substrates, the ensemble decay follows a power-law of time, the exponent being the difference of the power-law exponents of on- and off-time distributions. The decay exponent is also found to depend on substrate. We discuss possible mechanisms for this dependence, in conjunction with previously published models. (C) 2004 Elsevier B.V. All rights reserved.