Temporal evolution of double layers in pulsed helicon plasmas

Biloiu, Ioana A.; Scime, Earl E.
August 2009
Applied Physics Letters;8/3/2009, Vol. 95 Issue 5, p051504
Academic Journal
Delays of the order of tens of milliseconds in the appearance of the fast argon ion population in the expansion region of a pulsed helicon plasma are observed in time-resolved, laser induced fluorescence measurements. The fast ion population is a proxy for the presence of a double layer. The magnitude of the time delay depends strongly on the length of the interval between plasma pulses; the shorter the time between pulses, the shorter the time delay. The time delay approaches zero for inter-pulse intervals smaller than 30 ms. The double layer strength is not affected by plasma source modulation frequency.


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