Fluorescence properties of thick shell CdSe/CdS quantum dots at cryogenic temperature

The blinking of fluorophore, that means the switch between bright and dark states, is a well-known phenomenon for single emitters. In the case of standard CdSe/ZnS colloidal quantum dots (QDs), this was considered as their main drawback for experiments at the single molecule level. Statistical analysis of these intensity fluctuations has demonstrated that the dark states duration exhibits a universal heavy-tailed power law distribution. Long off-periods, of the order of the time experiment, are always observed.