Superposition Principle in Auger Recombination of Charged and Neutral Multicarrier States in Semiconductor Quantum Dots

	Superposition Principle in Auger Recombination of Charged and Neutral Multicarrier States in Semiconductor Quantum Dots
	Klimov, Victor I.1; Lim, Jaehoon 1; Wu, Kaifeng 1,2
刊名	ACS NANO
	2017-08-01
卷号	11 期号:8 页码:8437-8447
关键词	colloidal quantum dots positively and negatively charged quantum dots Auger recombination multiexcitons positive and negative trions
英文摘要	Application of colloidal semiconductor quantum dots (QDs) in optical and optoelectronic devices is often complicated by unintentional generation of extra charges, which opens fast nonradiative Auger recombination pathways whereby the recombination energy of an exciton is quickly transferred to the extra carrier(s) and ultimately dissipated as heat. Previous studies of Auger recombination have primarily focused on neutral and, more recently, negatively charged multicarrier states. Auger dynamics of positively charged species remains more poorly explored due to difficulties in creating, stabilizing, and detecting excess holes in the QDs. Here we apply photochemical doping to prepare both negatively and positively charged CdSe/CdS QDs with two distinct core/shell interfacial profiles ("sharp" versus "smooth"). Using neutral and charged QD samples we evaluate Auger lifetimes of biexcitons, "negative and positive trions (an exciton with an extra electron or a hole, respectively), and multiply negatively charged excitons. Using these measurements, we demonstrate that Auger decay of both neutral and charged multicarrier states can be presented as" a superposition of independent elementary three=partide Auger events. As one of the manifestations of the superposition principle, we observe that the biexciton Auger decay rate can be presented as a sum of the Auger rates for independent negative and positive trion pathways. By comparing the measurements on the QDs with the "sharp" versus "smooth" interfaces, we also find that while affecting the absolute values of Auger lifetimes, manipulation of the shape of the confinement potential does not lead to violation of the superposition principle, which still allows us to accurately predict the biexciton Auger lifetimes based on the measured negative and positive trion dynamics. These findings indicate considerable robustness of the superposition principle as applied to Auger decay of charged and" neutral multicarrier states, suggesting its generality to quantum-confined nanocrystals of arbitrary compositions and complexities.
WOS标题词	Science & Technology ; Physical Sciences ; Technology
类目[WOS]	Chemistry, Multidisciplinary ; Chemistry, Physical ; Nanoscience & Nanotechnology ; Materials Science, Multidisciplinary
研究领域[WOS]	Chemistry ; Science & Technology - Other Topics ; Materials Science
关键词[WOS]	LIGHT-EMITTING-DIODES ; CORE-SHELL INTERFACE ; HOT-CARRIER TRANSFER ; CDSE NANOCRYSTALS ; BLINKING ; MULTIPLICATION ; BIEXCITONS ; SUPPRESSION ; PERFORMANCE ; EXCITATION
收录类别	SCI
语种	英语
WOS记录号	WOS:000408520900098
内容类型	期刊论文
源URL	[http://cas-ir.dicp.ac.cn/handle/321008/149990]
专题	大连化学物理研究所_中国科学院大连化学物理研究所
作者单位	1.Los Alamos Natl Lab, Chem Div, Los Alamos, NM 87545 USA 2.Chinese Acad Sci, Dalian Inst Chem Phys, State Key Lab Mol React Dynam & Collaborat Innova, 457 Zhongshan Rd, Dalian 116023, Peoples R China
推荐引用方式 GB/T 7714	Klimov, Victor I.,Lim, Jaehoon,Wu, Kaifeng. Superposition Principle in Auger Recombination of Charged and Neutral Multicarrier States in Semiconductor Quantum Dots[J]. ACS NANO,2017,11(8):8437-8447.
APA	Klimov, Victor I.,Lim, Jaehoon,&Wu, Kaifeng.(2017).Superposition Principle in Auger Recombination of Charged and Neutral Multicarrier States in Semiconductor Quantum Dots.ACS NANO,11(8),8437-8447.
MLA	Klimov, Victor I.,et al."Superposition Principle in Auger Recombination of Charged and Neutral Multicarrier States in Semiconductor Quantum Dots".ACS NANO 11.8(2017):8437-8447.