Observation of enhanced WSe2 exciton-exciton annihilation in WSe2/Gr/hBN heterostructure

doi:10.1063/5.0180501

	Observation of enhanced WSe2 exciton-exciton annihilation in WSe2/Gr/hBN heterostructure
	Wang, Chen 1; Chen, Yu2 ; Sun, Kaiwen 1; Wang, Wei 1; Pu, Ruihua2 ; Lin, Xian 1; Liu, Weimin2 ; Ma, Guohong 1
	2024-01-29
发表期刊	APPLIED PHYSICS LETTERS
ISSN	0003-6951
卷号	124 期号:5
DOI	10.1063/5.0180501
摘要	Due to strong quantum confinement effects and novel physical properties, two-dimensional transition metal dichalcogenides (TMDCs) as well as their heterostructures provide an attractive platform for studying excitonic effects and many-body interactions. However, manipulation on the excitonic effect in TMDCs remains challenge owing to the complex interplay of various factors. In this Letter, we report large exciton peak redshift and enhanced exciton-exciton annihilation in WSe2/Gr/hBN heterostructures investigated with static and transient optical spectroscopy. The pronounced redshift of exciton energy in the triple layer heterostructure arises from the charge transfer effect between graphene and WSe2, which leads to the reduction of the WSe2 exciton binding energy significantly due to the Coulomb screening effect. As a result, the reduced exciton binding energy increases the exciton delocalization in the WSe2 layer, leading to an increased probability of exciton-exciton collisions, which results in fast exciton annihilation rate. This study demonstrates the impact of graphene layer on exciton energy as well as the relaxation dynamics in WSe2/Gr/hBN heterostructures, which provides insights into the understanding of quasiparticle physics and many-body interactions in 2D materials. © 2024 Author(s).
关键词	Annihilation Binding energy Charge transfer Graphene Selenium compounds Transition metals Tungsten compounds Dichalcogenides Exciton energies Exciton peak Exciton-binding energy Exciton-exciton annihilation Excitonic effect Many-body interactions Quantum confinement effects Red shift Two-dimensional
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收录类别	EI
语种	英语
出版者	American Institute of Physics Inc.
EI入藏号	20240615500052
EI主题词	Excitons
EI分类号	531 Metallurgy and Metallography ; 761 Nanotechnology ; 801.4 Physical Chemistry ; 802.2 Chemical Reactions ; 804 Chemical Products Generally ; 932.1 High Energy Physics
原始文献类型	Journal article (JA)
引用统计
文献类型	期刊论文
条目标识符	https://kms.shanghaitech.edu.cn/handle/2MSLDSTB/349730
专题	物质科学与技术学院物质科学与技术学院_PI研究组_刘伟民组物质科学与技术学院_博士生
通讯作者	Ma, Guohong
作者单位	1.Department of physics, Shanghai University, Shanghai; 200444, China 2.School of Physical Science and Technology, ShanghaiTech University, Shanghai; 201210, China
推荐引用方式 GB/T 7714	Wang, Chen,Chen, Yu,Sun, Kaiwen,et al. Observation of enhanced WSe2 exciton-exciton annihilation in WSe2/Gr/hBN heterostructure[J]. APPLIED PHYSICS LETTERS,2024,124(5).
APA	Wang, Chen.,Chen, Yu.,Sun, Kaiwen.,Wang, Wei.,Pu, Ruihua.,...&Ma, Guohong.(2024).Observation of enhanced WSe2 exciton-exciton annihilation in WSe2/Gr/hBN heterostructure.APPLIED PHYSICS LETTERS,124(5).
MLA	Wang, Chen,et al."Observation of enhanced WSe2 exciton-exciton annihilation in WSe2/Gr/hBN heterostructure".APPLIED PHYSICS LETTERS 124.5(2024).