UV laser irradiation of IR laser generated particles ablated from nitrobenzyl alcohol
Particles generated by 2.94 μm pulsed IR laser ablation of liquid 3-nitrobenzyl alcohol were irradiated with a 351 nm UV laser 3.5 mm above and parallel to the sample target. The size and concentration of the ablated particles were measured with a light scattering particle sizer. The application of the UV laser resulted in a reduction in the average particle size by one-half and an increase in the total particle concentration by a factor of nine. The optimum delay between the IR and UV lasers was between 16 and 26 μs and was dependent on the fluence of the IR laser: higher fluence led to a more rapid appearance of particulate. The ejection velocity of the particle plume, as determined by the delay time corresponding to the maximum two-laser particle concentration signal, was 130 m/s at 1600 J/m 2 IR laser fluence and increased to 220 m/s at 2700 J/m 2 . The emission of particles extended for several ms. The observations are consistent with a rapid phase change and emission of particulate, followed by an extended emission of particles ablated from the target surface. © 2009 Elsevier B.V. All rights reserved.
Publication Source (Journal or Book title)
Applied Surface Science
Fan, X., & Murray, K. (2009). UV laser irradiation of IR laser generated particles ablated from nitrobenzyl alcohol. Applied Surface Science, 255 (12), 6297-6302. https://doi.org/10.1016/j.apsusc.2009.02.005