Effect of sample position on collinear femtosecond double-pulse laser-induced breakdown spectroscopy of silicon in air
Effect of sample position on collinear femtosecond double-pulse laser-induced breakdown spectroscopy of silicon in air
复制标题
样品位置对空气中硅共线飞秒双脉冲激光诱导击穿光谱的影响
DOI：
10.1039/c4ja00006d
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发表时间：
2014
影响因子：
3.4
通讯作者：
Ding Dajun
中科院分区：
文献类型：
--
作者：
Qi Hongxia;Li Suyu;Qi Ying;Chen Anmin;Hu Zhan;Huang Xuri;Jin Mingxing;Ding Dajun
利用飞秒双脉冲激光在空气中诱导硅等离子体。激光波长为800 nm。飞秒双脉冲的脉冲间延迟从-20 ps到100 ps。在实验过程中，光谱线被固定在288.157 nm的波长处。通过选择合适的样品位置，观察到发射强度显著增加。样品位置的范围为5.17 ~ 5.27 mm，且高能量密度和低能量密度下的最佳样品位置不同。在较高的激光能量密度下，对于双脉冲的所有脉冲间延迟，在最佳焦点位置的两侧都可以获得最佳的发射强度。这一现象可以用飞秒激光脉冲在空气中的非线性传输来解释。在较低的激光能量密度下，随着双脉冲的脉冲间延迟的增加，最佳取样位置由一侧向两侧变化。结果表明，在飞秒双脉冲激光诱导击穿光谱的背景下，样品位置的效果可以特别有利。该研究将进一步提高飞秒双脉冲激光的应用水平。
A femtosecond double-pulse laser was used to induce the plasma of silicon in air. The laser wavelength was 800 nm. The interpulse delay of the femtosecond double-pulse was from −20 ps to 100 ps. During the experiment, the spectral line was fixed at the wavelength of 288.157 nm. The emission intensity was observed to lead to a significant increase by choosing the proper sample position. The range of the sample position is from 5.17 mm to 5.27 mm. And, the best sample position for the higher laser fluence was different from the position for the lower laser fluence. At the higher laser fluence, the optimized emission intensity can be obtained at either side of the best focal position for all interpulse delays of the double-pulse. The phenomena can be explained by the nonlinear propagation of the femtosecond laser pulse in air. At the lower laser fluence, the best sample position will change from one side to both sides with the increase of the interpulse delay of the double-pulse. The results showed that the effect of the sample position can be especially advantageous in the context of femtosecond double-pulse laser-induced breakdown spectroscopy. The study will lead a further improvement in the applications of the femtosecond double-pulse laser.