Emission characteristics of gadolinium plasma in orthogonal double-pulse laser breakdown spectroscopy using femto and nanosecond laser (Contract research)

The effects of the air plasma on the emission characteristics of Gd plasma were studied in double-pulse LIBS with a femtosecond laser as an ablation source and data required for optimization of the LIBS were collected. As a result, about 200-times higher emission intensity in the double-pulse reheating mode was obtained than the emission in the single-pulse method. And the optimum ablation laser focus position was about 9 mm from the sample surface, and the emission was maximized with the δx of 1.0-1.2 mm and δy of 0.5-1.0 mm. Moreover, it was also shown that the emission intensity was highest at the pulse delay time of 8 μs with the δx of 1.0 mm and δy of 0.5 mm. The spectral width of the emission did not depend on the reheating laser pulse energy, and the high emission intensity could be obtained without the spectral broadening. (author)