Measurement of the radiative and non-radiative decay rates of single   CdSe nanocrystals through controlled modification of their spontaneous   emission
  We present a simple method to measure the radiative and non-radiative recombination rates of individual fluorescent emitters at room temperature. By placing a single molecule successively close and far from a dielectric interface and simultaneously measuring its photoluminescence decay and its orientation, both the radiative and non-radiative recombination rates can be determined. For CdSe nanocrystals, our results demonstrate that the fluorescence quantum efficiency, determined at the single molecule level, is 98% in average, far above the value expected from conventional ensemble experiments. The bi-dimensionnal nature of the transition dipole is also directly evidenced from a single particle measurement. 
X. Brokmann, (LKB - Lhomond), L. Coolen (LKB - Lhomond), Maxime Dahan   (LKB - Lhomond), J.P. Hermier (LKB - Lhomond)