光强可调的变温荧光测试系统在准二维钙钛矿中的应用  

Application of variable temperature fluorescence test system with adjustable pump intensity in quasi-2D perovskite materials

作　　者：张博[1] 郭秀文 崔明焕[1] 孙铭泽 李高强 周静[1] 秦朝朝(导师)[1] ZHANG Bo;GUO Xiuwen;CUI Minghuan;SUN Mingze;LI Gaoqiang;ZHOU Jing;QIN Chaochao(Henan Key Laboratory of Infrared Materials&Spectrum Measures and Applications,College of Physics,Henan Normal University,Xinxiang 453007,China)

机构地区：[1]河南师范大学物理学院,河南省红外材料与光谱测量应用重点实验室,河南新乡453007

出　　处：《量子电子学报》2021年第4期420-427,共8页Chinese Journal of Quantum Electronics

基　　金：国家自然科学基金,11804084;河南省科技攻关研究项目,182102210369;河南省教育厅重点项目,19A140011;河南省高等学校青年骨干教师培养计划,2019GGJS065。

摘　　要：激子性质对准二维钙钛矿材料的发光机理具有决定性影响。测量激子-声子耦合强度和激子结合能是研究准二维钙钛矿材料激子特性的有力手段,可以为揭示其内部光发射机制和进一步提高荧光量子产率提供关键的科学依据。将变光强荧光测试系统和液氮恒温装置相结合,利用LABVIEW程序进行系统控制,搭建了一套光强可调的变温荧光测试系统,并以准二维钙钛矿薄膜样品为研究对象,开展了对准二维钙钛矿的激子及其发光性质的研究。研究结果表明:随着准二维钙钛矿材料值的增加,激子-纵向光学声子耦合强度和激子结合能均逐渐降低。此外,利用该测试系统进行了室温下变光强荧光测量,探究了准二维钙钛矿薄膜的光学增益,得到其放大的自发辐射阈值为3.2 μJ/cm^(2)。Exciton properties have a decisive influence in the luminescence mechanism of quasi-2 D perovskite material.Measurement of exciton-phonon coupling strength and exciton binding energy is a powerful means of investigating exciton properties of quasi-two-dimensional perovskite materials,which can provide a key scientific basis for revealing the internal light emission mechanism and further improving the fluorescence quantum yield.By combining the adjustable pump intensity fluorescence testing system with the liquid nitrogen thermostat,a set of variable temperature fluorescence test system with adjustable pump intensity is built and controlled by the LAB VIEW program.Then the exciton and luminescence properties of quasi two-dimensional perovskite film samples are studied by using the built system.The experimental results show that the exciton-longitudinal optical phonon coupling strength and exciton binding energy decrease with the increase of<n>-value of quasi-two-dimensional perovskite.In addition,by measuring the adjustable pump intensity fluorescence at room temperature with the built system,the optical gain of quasi-two-dimensional perovskite films is explored,and it is shown that the amplified threshold of spontaneous emission of the film is 3.2μJ/cm^(2).

关 键 词：光谱学 激子性质 变温荧光 准二维钙钛矿 放大的自发辐射 

分 类 号：O433.1[机械工程—光学工程]