Effect of pulse duration in multi-pulse excitation of silicon in laser-induced breakdown spectroscopy (LIBS).

The aim of this study is to investigate the mechanisms responsible for the increase in ablated mass and signal enhancement observed on multi-pulse excitation. Several experiments were designed to obtain evidence that confirms the laser-sample and/or laser-plasma interaction, with special attention to the role of the pulse width on these effects. A train of pulses, with a separation of a few microseconds between pulses, was used for laser-induced breakdown spectroscopy (LIBS) analysis.