Extinction of 10.6 μm laser radiation by free electrons in an argon discharge at atmospheric pressure

Inverse BremsstrahlungNegative lens effectStark Broadening

Park, Sehyun ; Eden ; James Gary

关键词: Inverse BremsstrahlungNegative lens effectStark Broadening;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/92855/PARK-THESIS-2016.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Experiments will be described in which the extinction of 10.6 μm photons by free electrons in a single filamentary discharge is studied. The extinction ranges from 3 to 10 percent over a path length of 1 cm, depending on the argon flow rate. The spatio-temporally averaged electron density in the filament is more than 10^15 cm^(-3), as determined by Stark broadening of the hydrogen alpha (656.28 nm) and 4p'[1/2]-4s[3/2]^0 argon I (696.54 nm) lines. Experiments indicate that the observed extinction of 10.6 μm is attributable to a combination of inverse bremsstrahlung and a negative lens effect, and the results will be compared to theoretical calculations based on Boltzmann's equation. The potential application of such high electron density plasmas to studies of fundamental plasma phenomena, as well as optical applications, will be discussed.