Optoelectronic modulation of a laser interferometer in the infrared for accurate electron density variation measurements.
An improved method for high-electron-density (10(17) cm(-3)) measurement in a shock-generated plasma is described. A laser interferometer operated at 3.39 mum is regularly modulated (1 MHz) by a LiNbO(3) electro-optical crystal. Thus electron-density variations of 8x10(15) cm(-3) mus(-1) and fluctuation of 8x10(14) cm(-3) can be simultaneously and accurately measured in a 4x4-cm conventional shock tube. Experimental results in reflected shock waves are presented.
Lesage
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A
D.E.P.E.G. Observatoire de Meudon, 92190 Meudon, France.
Richou
J
J
Charil
P
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Combier
M
M
Lebrun
J L
JL