Open AccessExperimental diagnosis of electron density of laser induced air plasma by interferometry
Author(s) -
Hongchao Zhang,
Junfeng Lu,
Xiaowu Ni
Publication year - 2009
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.58.4034
Subject(s) - plasma , plasma channel , electron density , interferometry , laser , electron , materials science , atomic physics , interference (communication) , plasma parameters , plasma parameter , physics , optics , plasma diagnostics , nanosecond , channel (broadcasting) , electrical engineering , quantum mechanics , engineering
High quality interference pattern was obtained with a modified Mach-Zehnder interferomenter. An FFT analysis is applied to extracting the phase of the reconstructed interferograms, and then the inverse Abel transformation is used to calculate the three-dimensional electron density distribution. The electron density and the plasma expanding velocity at various delay times were obtained. The results show that the formation of the plasma channel in the early stage of the laser induces air plasma, and the rapid decrease of the plasma expanding velocity accelerates the collapse of the plasma channel. At about 48 nanosecond time, the eccentricity of the plasma shape reaches the maximum value and then evolves to a circular shape.