Nanostructured Al/PtAl∕Pt multilayer films were ignited by single pulse irradiation from a Ti:sapphire femtosecond laser system. Critical ignition fluences (0.9–22 J/cm2)(0.9–22J∕cm2) required to initiate a self-propagating reaction were quantified for different multilayer designs. Multilayers with smaller bilayer thickness required relatively lower fluence for ignition. Ignition threshold fluence was also found to be 1.4–3.6 times higher for Al-capped multilayers than for Pt-capped multilayers. Ablation threshold fluences were measured for Al (860±70 mJ/cm2)(860±70mJ∕cm2) and Pt (540±50 mJ/cm2)(540±50mJ∕cm2) and related to the observed difference in ignition fluences for Al- and Pt-capped multilayers.
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