Zhou Pingwei, Zhu Yu, Li Shengfu, Zhu Li-Guo
Institute of Fluid Physics, China Academy of Engineering Physics Mianyang Sichuan 621900 P. R. China
RSC Adv. 2018 Dec 17;8(73):41915-41919. doi: 10.1039/c8ra06985a. eCollection 2018 Dec 12.
A method that can reutilize the energy of a nanosecond pulse laser beam and its performance in single particle triggered laser induced breakdown spectroscopy (LIBS) were studied. The propagation direction of the laser beam (Nd-YAG laser, 1064 nm, 9 ns and 0-80 mJ) was changed in an appropriate way and the energy overlapped at one point in space. In this setup, the energy used to break down pure air was reduced by 25% and the emission intensity of air plasma improved by 220% under the same pulse energy. Besides, the plasma temperature estimated by the relative line-to-continuum intensity ratio was improved by almost 900 K at 20 mJ. Furthermore, this method was applied in single particle triggered LIBS. NaCl particles with a diameter of ∼10 μm were used as the target sample and the scattered light of an 808 nm continuous laser beam was employed as a trigger signal to trigger the Nd-YAG laser. The emission line intensity of Na element was enhanced by 200%. This method can not only improve the emission intensity of a gas sample but can also be applied to single particle samples and has great significance in the application of ns-LIBS and the research and development of portable LIBS equipment.
研究了一种可重新利用纳秒脉冲激光束能量的方法及其在单颗粒触发激光诱导击穿光谱（LIBS）中的性能。以适当方式改变激光束（Nd-YAG激光，1064 nm，9 ns，0 - 80 mJ）的传播方向，使能量在空间中的一点重叠。在此设置下，在相同脉冲能量下，用于击穿纯空气的能量降低了25%，空气等离子体的发射强度提高了220%。此外，在20 mJ时，通过相对线与连续谱强度比估算的等离子体温度提高了近900 K。此外，该方法应用于单颗粒触发LIBS。使用直径约为10μm的NaCl颗粒作为目标样品，并采用808 nm连续激光束的散射光作为触发信号来触发Nd-YAG激光。Na元素的发射线强度提高了200%。该方法不仅可以提高气体样品的发射强度，还可应用于单颗粒样品，在ns-LIBS的应用以及便携式LIBS设备的研发中具有重要意义。
