Tailored Ultrafast Pulses for Selective Energetic Residue Sampling; Final rept. Oct 2006-Sep 2007

摘要

Femtosecond pulses offer several advantages over more conventional nanosecond pulses for laser-induced breakdown spectroscopy applications. These advantages include improved ablation, lower breakdown threshold, more efficient energy deposition, and less thermal damage to surrounding areas. The scope of this work is to determine if femtosecond laser-induced breakdown spectroscopy offers advantages for detecting trace explosive residues. Also, additional laser pulses, focused and nonfocused, were used to enhance the emission signal. It was determined that the lower breakdown threshold was the most important characteristic of the femtosecond pulse for, explosive residue detection. Enhancement of the plasma becomes more critical if lower-energy pulses are used since emission intensity is sacrificed.