Abstract

A XeCl excimer laser (20 ns, 10 mJ) was focused on a copper target at a relatively high power density (1010 W/cm2) in a surrounding gas of air in the pressure range from 1 Torr to about 10 Torr. Plasma characteristics were examined in detail with the use of a time-resolved spatial distribution technique on the emission lines Cu(I) 5218 A, Cu(I) 5105 A, and Cu(II) 4674 A. The results show that the majority of atoms are ablated in the form of neutral atoms, and that the temperature of the plasma increases with time in the initial explosion stage. These facts suggest that the secondary plasma is excited by a shock wave and the recombination emission process is not predominant. It was also demonstrated that the plasma produced at 1 Torr is due to another excitation mechanism; namely, the collision of ultrafast atoms with surrounding gas molecules. This plasma is also suitable for analytical spectrochemical application.

Novel control of plasma expansion direction aimed at very low pressure laser-induced plasma spectroscopy

Soo-Jin Choi, Jae-Jun Choi, and Jack J. Yoh
Opt. Express 23(5) 6336-6344 (2015)

Direct evidence of laser-induced shock wave plasma from organic targets in low pressure He ambient gas, showing the effect of target hardness on its propagation speed and the resulted spectral performance

Kurnia Lahna, Marincan Pardede, Koo Hendrik Kurniawan, Kiichiro Kagawa, and May On Tjia
Appl. Opt. 56(36) 9876-9881 (2017)

Formation and emission characteristics of CN molecules in laser induced low pressure He plasma and its applications to N analysis in coal and fossilization study

Kurnia Lahna, Rinaldi Idroes, Nasrullah Idris, Syahrun Nur Abdulmadjid, Koo Hendrik Kurniawan, May On Tjia, Marincan Pardede, and Kiichiro Kagawa
Appl. Opt. 55(7) 1731-1737 (2016)

Laser-induced plasma peculiarity at low pressures from the elemental lifetime perspective

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Opt. Express 19(23) 23097-23103 (2011)

Laser-induced plasma imaging for low-pressure detection

H. Yuan, Igor B. Gornushkin, Ardian B. Gojani, X. H. Wang, and M. Z. Rong
Opt. Express 26(12) 15962-15971 (2018)