Accuracy improvement of quantitative analysis by spatial confinement in laser-induced breakdown spectroscopy

Authors

L. B. Guo, Huazhong University of Science and Technology,University of Nebraska-Lincoln
Z. Q. Hao, Huazhong University of Science and Technology
M. Shen, Huazhong University of Science and Technology
W. Xiong, University of Nebraska-Lincoln
X. N. He, University of Nebraska-Lincoln
Z. Q. Xie, University of Nebraska-Lincoln
M. Gao, Huazhong University of Science and TechnologyFollow
X. Y. Li, Huazhong University of Science and Technology
X. Y. Zeng, Huazhong University of Science and Technology
Yongfeng Lu, University of Nebraska-LincolnFollow

Date of this Version

7-29-2013

Citation

Optics Express 21:15 (2013), pp. 18188 - 18195; doi:10.1364/OE.21.018188

Comments

Copyright © 2013 Optical Society of America. Used by permission.

Abstract

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/cm2 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.