Dynamics of double plume emissions in TEA-CO2 laser ablation of graphite
Document Type
Article
Publication Date
1-1-2003
Abstract
Streak photography of TEA-CO2 laser ablation of graphite in helium (He) and argon (Ar) background gases shows two luminous fronts, that are spatially and temporally separated, lifting off the graphite target. The velocity profile of the second front appears to follow closely that of the first luminous front. The second front is absent if the laser-supported absorption wave sets in when the background gas pressure is increased to 50-mbar Ar. The optical emission spectroscopy display many of triply, doubly, and singly ionized carbon species in the expanding plume at < 0.3 mbar He, while the excited and singly ionized helium species are found in (1-30) mbar He which coincides with streak observations of strong luminous fronts. Computer simulations of the propagation trajectories of luminous fronts are carried out using the blast-wave, drag, and the snowplow models.
Keywords
Dynamics, Laser ablation, Optical emission, Plume species, Computer simulation, Dry etching, Dye lasers, Emission spectroscopy, Graphite, Helium, Mathematical models, Streak cameras, Superconducting materials, Thermal plumes, Thin films, Full-width at half-maximum (FWHM)
Divisions
PHYSICS
Publication Title
IEEE Transactions on Plasma Science
Volume
31
Issue
6
Publisher
Institute of Electrical and Electronics Engineers (IEEE)