3. Semiconductor nanocrystals with 100% quantum efficiency

3.1 Reduced flicker – Increased quantum efficiency

We have already seen that non-radiative Auger recombination processes appear to play a decisive role in the poor quantum efficiency of nanocrystals. Recall that Auger recombination corresponds to the non-radiative transfer of energy from an exciton to an isolated charge carrier present in the nanocrystal.

To increase the quantum efficiency of nanocrystals, Auger recombinations must be made less likely. If these become a minority compared with radiative recombinations, the emission of a photon by exciton recombination will be more likely.

Two approaches have been studied with the aim of reducing the efficiency of Auger processes: composition gradient structures and thick-shell structures....