Spectroscopic study on the time evolution behaviors of the double laser-induced breakdown of Al plasma

To study the time evolution characteristics of plasma fluorescence, aluminum feature spectrum was measured and analyzed through dual-pulse laser-induced breakdown spectroscopy in the standard ambient temperature and pressure experimental conditions. Two Nd:YAG lasers were used to perform the experiment; one laser ablated the target, and the other reheated the plasma in air. The plasma emission intensity was enhanced at an optimal inter-pulse delay time of 200ns. The plasma fluorescence lifetime was measured in a dual-pulse laser excitation mode at different inter-pulse delays. The plasma fluorescence lifetime changed with the changing of inter-pulse delay under double pulse excitation. The results can further understand of the time evolution of the plasma under double-pulse laser excitation.