Abstract

Microplasmas produced by lasers operating in the ultraviolet are unusual because of their low threshold requirements on laser pulse energy and their short lifetimes (microplasma lifetimes as short as 100 ns have been observed). These laser-produced microplasmas have been used as ignition sources for reactive gases and as the working media in techniques for chemical analysis (particularly in conjunction with gas chromatography). In order to better understand the details of microplasma initiation and growth and to extend their range of usefulness, time-resolved spectroscopic measurements are being conducted. Specifically, atomic and ionic emissions from hydrogen, carbon, oxygen, and chlorine are being analyzed to determine the microplasma temperatures and electron densities. Knowledge of these parameters provides important insight into the excitation and equilibrium characteristics of the microplasmas, information that is neces­sary for their analytical applications.

© 1992 Optical Society of America