Towards zero-threshold optical gain using charged semiconductor quantum dots

doi:10.1038/NNANO.2017.189

	Towards zero-threshold optical gain using charged semiconductor quantum dots
	Wu, Kaifeng 2,3; Park, Young-Shin 1,2; Lim, Jaehoon 2; Klimov, Victor I.2
刊名	NATURE NANOTECHNOLOGY
	2017-12-01
卷号	12 期号:12 页码:1140-+
ISSN号	1748-3387
DOI	10.1038/NNANO.2017.189
文献子类	Article
英文摘要	Colloidal semiconductor quantum dots are attractive materials for the realization of solution-processable lasers. However, their applications as optical-gain media are complicated by a non-unity degeneracy of band-edge states, because of which multiexcitons are required to achieve the lasing regime. This increases the lasing thresholds and leads to very short optical gain lifetimes limited by nonradiative Auger recombination. Here, we show that these problems can be at least partially resolved by employing not neutral but negatively charged quantum dots. By applying photodoping to specially engineered quantum dots with impeded Auger decay, we demonstrate a considerable reduction of the optical gain threshold due to suppression of ground-state absorption by pre-existing carriers. Moreover, by injecting approximately one electron per dot on average, we achieve a more than twofold reduction in the amplified spontaneous emission threshold, bringing it to the sub-single-exciton level. These measurements indicate the feasibility of 'zero-threshold' gain achievable by completely blocking the band-edge state with two electrons.
WOS关键词	AMPLIFIED SPONTANEOUS EMISSION ; AUGER RECOMBINATION ; ROOM-TEMPERATURE ; STIMULATED-EMISSION ; CDSE NANOCRYSTALS ; LIGHT-EMISSION ; LASERS ; SUPPRESSION ; PERFORMANCE ; INTERFACE
WOS研究方向	Science & Technology - Other Topics ; Materials Science
语种	英语
出版者	NATURE PUBLISHING GROUP
WOS记录号	WOS:000417280400017
内容类型	期刊论文
源URL	[http://cas-ir.dicp.ac.cn/handle/321008/168428]
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
通讯作者	Klimov, Victor I.
作者单位	1.Univ New Mexico, Ctr High Technol Mat, Albuquerque, NM 87131 USA 2.Los Alamos Natl Lab, Chem Div, Los Alamos, NM 87545 USA 3.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	Wu, Kaifeng,Park, Young-Shin,Lim, Jaehoon,et al. Towards zero-threshold optical gain using charged semiconductor quantum dots[J]. NATURE NANOTECHNOLOGY,2017,12(12):1140-+.
APA	Wu, Kaifeng,Park, Young-Shin,Lim, Jaehoon,&Klimov, Victor I..(2017).Towards zero-threshold optical gain using charged semiconductor quantum dots.NATURE NANOTECHNOLOGY,12(12),1140-+.
MLA	Wu, Kaifeng,et al."Towards zero-threshold optical gain using charged semiconductor quantum dots".NATURE NANOTECHNOLOGY 12.12(2017):1140-+.