Spatial-confinement effects in laser-induced breakdown spectroscopy

Abstract

The space-confinement effects of laser-induced plasmas have been investigated by optical emission spectra (OES) and fast images. An obvious enhancement in the emission intensity of Al atomic lines was observed when a round pipe was placed around the laser-induced Al plasmas. The enhancement factor for the emission intensities of Al atomic lines was measured to be around 9 at the time delay of 12 µs when the pipe diameter is 10.8 mm. Assuming local thermodynamic equilibrium (LTE) conditions, the plasma temperature are estimated to be in the range of 4000 to 11000 K. It shows that the plasma temperature increased by around 1000 K when the space confinement occurred. Images of the laser-induced Al plasmas show that the plasmas were compressed into a smaller volume with the pipe presented. The mechanism of the space confinement was discussed.The space-confinement effects of laser-induced plasmas have been investigated by optical emission spectra (OES) and fast images. An obvious enhancement in the emission intensity of Al atomic lines was observed when a round pipe was placed around the laser-induced Al plasmas. The enhancement factor for the emission intensities of Al atomic lines was measured to be around 9 at the time delay of 12 µs when the pipe diameter is 10.8 mm. Assuming local thermodynamic equilibrium (LTE) conditions, the plasma temperature are estimated to be in the range of 4000 to 11000 K. It shows that the plasma temperature increased by around 1000 K when the space confinement occurred. Images of the laser-induced Al plasmas show that the plasmas were compressed into a smaller volume with the pipe presented. The mechanism of the space confinement was discussed.