Measurements of Laser-Induced Plasma and Optical Breakdown Spectra of Aluminium

Journal Article · Wed Nov 22 04:00:00 EST 2006 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2402757· OSTI ID:20895162

Parigger, Christian G ^[1]

---

1. University of Tennessee, Uiversity of Tennessee Space Institute (UTSI), Center for Laser Applications, 411 B. H. Goethert Parkway, Tullahoma, TN 37388 (United States)

Time-resolved spectroscopy is utilized in investigations of laser-induced optical breakdown plasma. Atomic and molecular features are analyzed for diagnostics applications in laser materials processing. The micro-plasma that is generated by nominal 1 to 10 nanosecond, focused laser radiation shows Stark broadened and shifted atomic lines early in the plasma decay. Subsequently, the emissions from the plasma reveal molecular recombination spectra. Analysis of the spectroscopic features allows one to infer species number densities and temperature. Measured spatial characteristics and post-breakdown fluid physics phenomena are numerically modeled using computational fluid dynamics. Electron number densities as high as 1019 cm-3 are found, determined from Stark widths and Stark shifts of hydrogen Balmer-alpha line. Stark broadened aluminium line spectra, following optical breakdown of solid aluminium, show electron number densities of typically 0.5 x 1019 cm-3 early in the plasma decay. The electron number densities for the aluminium experiments are inferred by comparison with hydrogen Balmer series lines.

• OSTI ID: 20895162
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 874; ISSN 0094-243X; ISSN APCPCS
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ALUMINIUM
BREAKDOWN
COMPUTERIZED SIMULATION
ELECTRON DENSITY
FLUID MECHANICS
HYDROGEN
LASER MATERIALS
LASER RADIATION
LASER-PRODUCED PLASMA
LINE BROADENING
PLASMA DIAGNOSTICS
PLASMA HEATING
PLASMA PRODUCTION
RECOMBINATION
SPECTROSCOPY
TIME RESOLUTION