Study on the Electron Density Distribution of Laser-Induced Air Plasmas
LIN Zhao-xiang1,CHEN Bo1,WU Jin-quan1,GONG Shun-sheng2,SUN Feng-lou1
1. College of Electrics and Information Engineering, South-Central University for Nationalities, Wuhan 430074, China 2. Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, National Key Lab of Magnetic Resonance and Atomic Physics，Wuhan 430071, China
Abstract：An 1.06 μm Nd∶YAG laser beam (energy: -500 mJ/pulse, pulse width: 10 ns, repetition rate: 30 Hz) was focused by a conical lens, and a column of laser-induced air plasmas (LIAP) came into being. The LIAP column, about 8 cm of long and 5 cm in maximal diameter, was studied by spectra measurement. The spectra of the LIAP column at different position were measured in the directions both perpendicular and parallel to the laser propagation respectively. From these data, the electron densities of the LIAP were evaluated. The experimental results indicate that the LIAP formed in an olivary shape, i.e., symmetrical in the vertical direction but unsymmetrical in the horizontal direction, and the maximal electron density is about 1018 cm-3. The spatial distributions of atoms, molecules and ions in different states in the LIAP were also discussed, and provide clues for discovering the microstructure of LIAP.
Key words：Laser-induced air plasmas;Spectral measurement;Electron density;Spatial distribution
林兆祥1,陈波1,吴金泉1,龚顺生2,孙奉娄1 . 激光大气等离子体的电子密度空间分布特性研究[J]. 光谱学与光谱分析, 2007, 27(01): 18-22.
LIN Zhao-xiang1,CHEN Bo1,WU Jin-quan1,GONG Shun-sheng2,SUN Feng-lou1 . Study on the Electron Density Distribution of Laser-Induced Air Plasmas. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2007, 27(01): 18-22.
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