摘要
Van der Waals heterostructures have recently emerged,in which two distinct transitional metal dichalcogenide(TMD)monolayers are stacked vertically to generate interlayer excitons(IXs),offing new opportunites for the design of optoelectronic devices.However,the bilayer heterostructure with type-II band alignment can only produce low quantum yield.Here,we present the observation of interlayer neutral excitons and trions in the MoSe_(2)/MoS_(2)/MoSe_(2)trilayer heterostructure(Tri-HS).In comparison to the 8 K bilayer heterostructure,the addition of a MoSe_(2)layer to the Tri-HS can significantly increase the quantum yield of IXs.It is believed the two symmetrical type-II band alignments formed in the Tri-HS could effectively promote the IX radiation recombination.By analyzing the photoluminescence(PL)spectrum of the IXs at cryogenic temperature and the power dependence,the existence of the interlayer trions was confirmed.Our results provide a promising platform for the development of more efficient optoelectronic devices and the investigation of new physical properties of TMDs.
基金
support from the National Natural Science Foundation of China(Nos.61775241,62090035,and U19A2090)
the Science and Technology Innovation Basic Research Project of Shenzhen(No.JCYJ20180307151237242)
Hunan Province Key Research and Development Project(No.2019GK2233)
Hunan Provincial Science Fund for Distinguished Young Scholars(No,2020JJ2059)
the Key Program of Science and Technology Department of Hunan Province(Nos.2019XK2001 and 2020XK2001)
the Youth Innovation Team(No,2019012)of Central South University
The authors are also thankful for the support of the High Performance Complex Manufacturing Key State Lab Project,Central South University(No.ZZYJKT2020-12)
Z.W.L.thanks the support from the Australian Research Council(ARC Discovery Project,No.DP180102976).
