γ射线辐照缺陷对单层MoS_(2)光谱学性质的调控研究  

Study on γ-Ray-Irradiated Defect Modulated Spectroscopic Properties of Monolayer MoS_2

作　　者：何俊材 李太申 佘泳志 姜郁飞 陈强 潘楠 HE Juncai;LI Taishen;SHE Yongzhi;JIANG Yufei;CHEN Qiang;PAN Nan(University of Science and Technology of China,Hefei National Research Center for Physical Sciences at the Microscale,Hefei 230026,China)

机构地区：[1]中国科学技术大学合肥微尺度物质科学国家研究中心,合肥230026

出　　处：《低温物理学报》2023年第1期13-21,共9页Low Temperature Physical Letters

基　　金：安徽省量子通信与量子计算机重大项目引导性项目(编号:AHY090200);中国科学院战略性先导科技专项(C类)(编号:XDC07010000)资助的课题。

摘　　要：围绕着过渡金属二硫族化合物(简称TMDs)材料的研究在近十年来一直是相关领域的热点.本文利用γ射线辐照,在单层MoS_(2)中引入辐照缺陷,利用光谱学手段结合原子力显微术研究辐照缺陷对单层MoS_(2)光谱性质和能谷特性的影响.结果表明,γ射线成功地在单层MoS_(2)中引入了辐照缺陷,辐照缺陷对其室温拉曼谱和光致发光谱(photoluminescence,简称PL)影响较小,但对其低温PL特性有显著影响,并且缺陷态束缚激子呈现出与自由激子截然不同的谷极化特性;相较于自由激子,缺陷态束缚激子的谷极化度对外加磁场的变化更为敏感,并在面外磁场>2 T时达到饱和,保持在约30%.The research on transition metal dichalcogenides(TMDs) has been a hotspot in the related fields in the past decade.In this work,high-energy γ-ray is used to introduce radiated defects into monolayer MoS_2.The effects of irradiated defects on the spectral and valley properties of monolayer MoS_2 are studied by optical spectra combined with atomic force microscopy.The results show that γ-ray successfully introduces irradiated defects into the monolayer MoS_2.These irradiated defects have limited effect on its room-temperature Raman spectrum and photoluminescence(PL) spectrum,but have a significant effect on its low-temperature PL.The defect-bound excitons show a valley polarization much different from the free excitons;compared with the latter,the valley polarization of the defect-bound exciton is more sensitive to the change of external magnetic field,and reaches saturation when the out-of-plane magnetic field is beyond SymbolqB@2 T,maintaining a degree of valley polarization of ~30%.

关 键 词：过渡金属二硫族化合物 Γ射线 缺陷 光致发光 谷极化 

分 类 号：TL816[核科学技术—核技术及应用]