Guo L B, Hao Z Q, Shen M, Xiong W, He X N, Xie Z Q, Gao M, Li X Y, Zeng X Y, Lu Y F
Wuhan National Laboratory for Optoelectronics (WNLO), Huazhong University of Science and Technology, Wuhan, Hubei 430074, China.
Opt Express. 2013 Jul 29;21(15):18188-95. doi: 10.1364/OE.21.018188.
To improve the accuracy of quantitative analysis in laser-induced breakdown spectroscopy, the plasma produced by a Nd:YAG laser from steel targets was confined by a cavity. A number of elements with low concentrations, such as vanadium (V), chromium (Cr), and manganese (Mn), in the steel samples were investigated. After the optimization of the cavity dimension and laser fluence, significant enhancement factors of 4.2, 3.1, and 2.87 in the emission intensity of V, Cr, and Mn lines, respectively, were achieved at a laser fluence of 42.9 J/cm(2) using a hemispherical cavity (diameter: 5 mm). More importantly, the correlation coefficient of the V I 440.85/Fe I 438.35 nm was increased from 0.946 (without the cavity) to 0.981 (with the cavity); and similar results for Cr I 425.43/Fe I 425.08 nm and Mn I 476.64/Fe I 492.05 nm were also obtained. Therefore, it was demonstrated that the accuracy of quantitative analysis with low concentration elements in steel samples was improved, because the plasma became uniform with spatial confinement. The results of this study provide a new pathway for improving the accuracy of quantitative analysis of LIBS.
为提高激光诱导击穿光谱定量分析的准确性，用Nd:YAG激光作用于钢靶产生的等离子体被一个腔室限制。研究了钢样品中多种低浓度元素，如钒（V）、铬（Cr）和锰（Mn）。在优化腔室尺寸和激光能量密度后，使用半球形腔室（直径：5 mm），在激光能量密度为42.9 J/cm²时，钒、铬和锰谱线的发射强度分别实现了4.2、3.1和2.87的显著增强因子。更重要的是，V I 440.85/Fe I 438.35 nm的相关系数从0.946（无腔室）提高到了0.981（有腔室）；对于Cr I 425.43/Fe I 425.08 nm和Mn I 476.64/Fe I 492.05 nm也得到了类似结果。因此，证明了钢样品中低浓度元素定量分析的准确性得到了提高，因为等离子体通过空间限制变得均匀。本研究结果为提高激光诱导击穿光谱定量分析的准确性提供了一条新途径。
