A quantitative method to analyze Mn2+-electron Auger processes in Mn2+-doped semiconductors has been developed and applied to evaluate Auger de-excitation rate constants in Mn2+-doped CdS nanocrystals. Analytical expressions have been derived that describe the Coulomb ('direct') and exchange ('sp-d') contributions to the Auger de-excitation rate constants. Using the results of density functional theory calculations as input, this analytical method was successfully applied to compute Auger rate constants for Mn2+:CdS nanocrystals that agree well with recent experimental measurements. From these calculations, we conclude that sp-d exchange coupling is primarily responsible for fast Auger de-excitation in Mn2+-doped semiconductors. Large e�CB-Mn2+(4s, 4p) hybridization is in large part responsible for the fact that the rate constants for eCB-Mn2+ Auger de-excitation in doped nanocrystals are as large as those for eCB-exciton Auger recombination in the corresponding undoped nanocrystals.

On the physical origins of fast Auger de-excitation in Mn<sup>2+</sup>-doped semiconductor nanocrystals

243rd National Meeting (2012)

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On the physical origins of fast Auger de-excitation in Mn2+-doped semiconductor nanocrystals

On the physical origins of fast Auger de-excitation in Mn²⁺-doped semiconductor nanocrystals