Ultrafast emission spectroscopy of exploding nanoaluminum in Teflon: Observations of aluminum fluoride

A multifunctional reactive material with Al nanoparticles and TeflonAF oxidizer is studied after laser flash-heating by time-resolved emission spectroscopy. At shorter times the emission is dominated by a broadband continuum peaked at 250 nm, originating from the Al core. At longer times, during an ablation process confined by thick optical windows, in addition to a broadband component, atomic Al emission bands and Al and AlF absorptions are observed. The AlF time dependence suggests that part of the AlF is created in the condensed-phase core and part in the dense plasma associated with confined ablation.