高重复频率激光剥离-火花诱导击穿光谱中原子辐射的时域特性研究  

Temporal Profiles of Atomic Emissions in High-Repetition-Rate Laser-Ablation Spark-Induced Breakdown Spectroscopy

作　　者：曹宇 康娟 陈钰琦 李润华 Cao Yu;Kang Juan;Chen Yuqi;Li Runhua(School of Physics and Optoelectronics,South China University of Technology,Guangzhou,Guangdong 510641,China)

机构地区：[1]华南理工大学物理与光电学院,广东广州510641

出　　处：《中国激光》2020年第6期307-313,共7页Chinese Journal of Lasers

基　　金：国家自然科学基金(61875055);中央高校基本科研业务费项目(SCUT-2018ZD45)。

摘　　要：为了了解在高重复频率激光剥离-火花诱导击穿光谱中原子辐射的时域特征,选择925银合金为样品,采用高重复频率激光剥离-火花诱导击穿光谱技术,通过实验研究了不同电容条件下Ag I 328.07 nm、Ag I 338.29 nm、Ag I 520.91 nm、Ag I 546.55 nm、Cu I 324.75 nm、Cu I 510.55 nm原子辐射谱线的时域图。尽管这些谱线对应于不同的上能级,但由于火花放电的作用,原子辐射在时域上表现出了非常相近的特点。原子辐射的维持时间和衰减特性主要由火花放电的电学参数决定,上能级的能量高低对它们的影响并不明显。在高重复频率激光剥离-火花诱导击穿光谱中,非门控信号记录模式下记录的光谱近似等效于门控信号记录模式下记录的光谱,可以用于开展元素的定量分析,这有助于降低该技术对门控光电探测器件的要求。For understanding the temporal profiles of the atomic emissions in high-repetition-rate laser-ablation spark-induced breakdown spectroscopy(HRR LA-SIBS),a 925 silver alloy sample was experimentally analyzed by HRR LA-SIBS.With different capacitances in the discharge circuit,the temporal profiles of atomic emissions of Ag I 328.07 nm,Ag I 338.29 nm,Ag I 520.91 nm,Ag I 546.55 nm,Cu I 324.75 nm,and Cu I 510.55 nm were experimentally studied.Under the excitation of the spark discharge,these six transitions exhibited close temporal profiles,even with different corresponding upper energy levels.The electric characteristics of the spark discharge were key factors that determine the persistence times and attenuation characteristics.Moreover,the influence of the upper energy level on them was negligible.In HRR LA-SIBS,the spectra recorded in non-gated signal recording mode were approximately equivalent to those recorded in gated signal recording mode for quantitative elemental analysis,which is helpful for simplifying the requirement of this technique for gated photon detectors.

关 键 词：光谱学 激光剥离-火花诱导击穿光谱 时间分辨 原子辐射 火花放电 

分 类 号：O433.4[机械工程—光学工程]