Time of flight of dual-laser ablation carbon plasmas by optical emission spectroscopy

Plasma emission induced by dual pulse laser ablation on graphite target was analyzed by time resolved optical spectroscopy. Experiments were carried out at a pressure of 10-5 Torr using two Nd : YAG lasers emitting at 1064 and 532 nm synchronized at up to 100 μs delay. Up to fivefold intensification of the C II emission lines was observed, when the delay between lasers was set in the 500–1000 ns range. From the time of flight measurements, the ion energy distribution could be controlled by changing the pulse delay between lasers.