Auger Recombination Suppression in Nanocrystals with Asymmetric Electron–Hole Confinement

Abstract
Type II and quasi‐type II nanocrystals with thick shells exhibit reduced blinking. However, after a number of monolayers, the influence of the shell thickness is found to vanish. Using a two‐band Kane Hamiltonian, it is shown that this behavior is a consequence of interband coupling and asymmetric confinement of electrons and holes. Interface alloying provides an additional, order‐of‐magnitude contribution to the Auger suppression, in agreement with recent experiments. The existence is predicted of critical shell thicknesses that strongly quench Auger processes for any core size.