Characterization of DC glow discharge plasma by nonlinear dynamical analysis tools

What is it about?

This paper reports plasma behavior, in an un-magnetized, co-axial electrode geometry DC glow discharge plasma system. Fluctuations and hysteresis in discharge characteristics have been observed when the electrode system has a central anode configuration. The important fact is that fluctuations and hysteresis in discharge characteristics are not observed in a central cathode configuration. The radial profile of plasma potential shows that it is less than the anode potential so that current continuity is maintained in this current-driven system. This paper also attempts to identify the source of order-to-chaos-to-order in floating potential (Vf) oscillations with respect to the discharge characteristics. When discharge current (Id) increases after the 1st negative differential resistance (NDR) region, the system self-organizes and stabilizes into a state of periodic oscillations. Chaotic behavior is a possible development of new dynamical states in the discharge, which develops from an initial high frequency, low amplitude oscillations (in the range 11.6 mA < Id < 15 mA) and thereafter transits to low frequency, large amplitude oscillations at Id > 15 mA. In the reverse path of discharge characteristics, the oscillations are more regular than in the forward path. Before the production of low frequency, large amplitude oscillations, the current oscillations follow a similar pattern to the floating potential oscillations. As it transits from chaotic to low frequency, large amplitude floating potential oscillations, discharge current oscillations show a chaotic type of behavior.

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Photo by Amos from Stockphotos.com on Unsplash

Photo by Amos from Stockphotos.com on Unsplash

Why is it important?

DC glow discharge, Sheaths, Nonlinear dynamical tools