Universal size-dependent trend in auger recombination in direct-gap and indirect-gap semiconductor nanocrystals.
We report the first experimental observation of a striking convergence of Auger recombination rates in nanocrystals of both direct- (InAs, PbSe, CdSe) and indirect-gap (Ge) semiconductors, which is in contrast to a dramatic difference (by up to 4-5 orders of magnitude) in the Auger decay rates in respective bulk solids. To rationalize this finding, we invoke the effect of confinement-induced mixing between states with different translational momenta, which diminishes the impact of the bulk-semiconductor band structure on multiexciton interactions in nanocrystalline materials.
Robel
István
I
Chemistry Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Gresback
Ryan
R
Kortshagen
Uwe
U
Schaller
Richard D
RD
Klimov
Victor I
VI