摘要
Interlayer excitons(IXS)are electron–hole pairs bound in the spatial separation layer by the Coulomb effect,and their lifetime is several orders of magnitude longer than that of direct excitons,providing an essential platform for long-lived exciton devices.The recent emergence of the van der Waals heterostructure(HS),which combines two layers of different transitional metal dichalcogenides(TMDs),has created new opportunities for IX research.Herein,we demonstrate the observation of double indirect interlayer excitons in the MoSe_(2)/WSe_(2)HS using photoluminescence(PL)spectroscopy.The intensities of the two peaks are essentially the same,and the energy difference is 22 meV,which is perfectly in line with the calculation result of density functional theory.Furthermore,the experience of variable excitation power also proves that the splitting of the IXs originates from the conduction band spin-splitting of MoSe_(2).The observation results provide a promising platform for further exploring the new physical properties and optoelectronic phenomena of TMD HS.
基金
the National Natural Science Foundation of China(No.61775241)
Hunan province key research and development project(No.2019GK2233)
the Hunan Science Fund for Distinguished Young Scholar(No.2020JJ2059)
Youth Innovation Team of Central South University(No.2019012)
Hunan Province Graduate Research and Innovation Project(No.CX20190177)
the Science and Technology Innovation Basic Research Project of Shenzhen(No.JCYJ20180307151237242)
Also,Y.P.L.acknowledges the support provided by the Central South University of the State Key Laboratory of High-Performance Complex Manufacturing Project(No.ZZYJKT2020-12)
Z.W.L.thanks the funding support from the Australian Research Council(ARC Discovery Projects)(Nos.DP210103539 and DP180102976).
