Electron density measurement by differential interferometry

Ding, W. X.; Brower, D. L.; Deng, B. H.; Yates, T.
October 2006
Review of Scientific Instruments;Oct2006, Vol. 77 Issue 10, p10F105
Academic Journal
A novel differential interferometer is being developed to measure the electron density gradient and its fluctuations. Two separate laser beams with slight spatial offset and frequency difference are coupled into a single mixer making a heterodyne measurement of the phase difference which is <1% of the total phase change experienced by each beam separately. This measure of the differential phase is made at multiple spatial points and can be inverted directly to provide the local density distribution.


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