Signal Enhancement in Laser-Induced Breakdown Spectroscopy Using Gated High-Voltage Pulses

We report here results obtained in a spark-assisted laser-induced breakdown spectroscopy (LIBS) experiment. In the conventional double-laser-pulse LIBS, one beam is often used to reheat the ablation plasma created by a pulsed laser. In this paper, the ablation plasma created by a pulsed laser is reheated using an electrical discharge. This is obtained from the discharge of a coaxial cable that is triggered by an ancillary laser. This setup produces a short duration, rectangular current pulse that applies as much as 0.75 MW of power to the ablation plasma. The application of the discharge produces an intensification of the atomic transitions emitted by the plasma by a factor of up to ~300. It was also found that ionic lines are intensified more strongly (by up to one order of magnitude more) than the neutral ones.