Laser-Induced Shock Wave Plasma in Glass and its Application to Elemental Analysis

Abstract

The characteristics of a laser-induced shock wave plasma which was induced by focusing a laser pulse on the surface of glass samples were examined by using radiation from a XeCl excimer laser and a TEA CO2 laser under reduced pressure of around 1 Torr. It was observed that shock wave plasma could not be generated by the TEA CO2 laser on low-melting-point glass because of the lack of expulsion from the sample surface. On the other hand, with the use of an excimer laser, shock wave plasma can be generated, even in low-melting-point glasses, thus making it amenable for spectrochemical analysis. Initial quantitative analysis was performed on a number of glass samples, and a linear calibration curve with a slope of near unity was obtained at a certain pressure. Furthermore, light elements such as Li and B, which are usually difficult to observe by the X-ray fluorescence method, were also successfully detected with a very low detection limit of less than 10 ppm. Other detection limits and background equivalent concentrations of almost all elements usually contained in glass, such as Na, Mg, Al, K, Ca, Ti, Zn, Zr, and Ba, were also presented. These results showed that the detection limit is much lower than those usually required for glass analysis.

Shock Excitation and Cooling Stage in the Laser Plasma Induced by a Q-Switched Nd:YAG Laser at Low Pressures

“…As we reported in previous studies, 25,26 the secondary plasma displays a characteristic symm etrical shape with brilliant color associated with the emission from the constituent atoms. In this case a visual inspection of the plasma also reveals a uniform distribution of green color with a nearly hemispherical shape for freely expanding plasma, and with a semicircular shape for con® ned plasma.…”

Excitation Mechanism in Laser-Induced Plasma at Atmospheric Air Pressure

“…As we have reported in our previous works [15][16][17][18][19][20][21][22][23][24][25][26][27], the secondary plasma and the primary plasma could be clearly observed by the naked eye in surrounding air below 10 Torr. The secondary plasma exhibited a characteristics hemispherical shape with brilliant colors associated with emissions from the constituent atoms, while the primary plasma displayed an intense white color associated with the continuum emission.…”

“…In a series of studies on the plasma generation process under reduced pressure [15][16][17][18][19][20][21][22][23][24][25], we found that a plasma having characteristics favorable to spectrochemical analysis can actually be generated by using a pulsed laser with short duration, such as the nitrogen laser, carbon dioxide laser, excimer laser and Nd-YAG laser, when the pressure of the surrounding gas is reduced to around 1 Torr. In these cases, the plasma invariably consists of two distinct parts.…”

Evaluation of the Potential of Laser-Induced Breakdown Spectroscopy for Detection of Trace Element in Liquid

“…However, its capability to provide remote, real-time measurement makes it especially suitable for application in hazardous or difficult environmental conditions such as waste treatment and industrial processing facilities. 6,8,9 LIBS has been applied to various solid samples, such as alloy, 10 glass, 11 paint, 12 and soil. 13 The application of LIBS in air sampling 14,15 and emission monitoring 6 also were reported.…”