Interplay between Auger and ionization processes in nanocrystal quantum dots.
We study the interplay between Auger effects and ionization processes in the limit of strong electronic confinement in core/shell CdSe/ZnS semiconductor nanocrystal quantum dots. Spectrally resolved fluorescence decay measurements reveal a monotonic increase of the photoluminescence decay rate on excitation density. Our results suggest that Auger recombination accelerates ionization processes that lead to the occupation of dark, nonemissive nanocrystal states. A model is proposed in the quantized Auger regime describing these experimental observations and providing an estimate of the Auger assisted ionization rates.
Kraus
Robert M
RM
Photonics and Optoelectronics Group, Physics Department and CeNS, Ludwig-Maximilians-Universität München, Amalienstr. 54, 80799 Munich, Germany.
Lagoudakis
Pavlos G
PG
Müller
Josef
J
Rogach
Andrey L
AL
Lupton
John M
JM
Feldmann
Jochen
J
Talapin
Dimitri V
DV
Weller
Horst
H