Chaos in atmospheric-pressure plasma jets

Abstract

Abstract:We report detailed characterization of a low-temperature atmosphericpressure plasma jet that exhibits regimes of periodic, quasi-periodic and chaotic behaviors. Power spectra, phase portraits, stroboscopic section and bifurcation diagram of the discharge current combine to comprehensively demonstrate the existence of chaos, and this evidence is strengthened with a nonlinear dynamics analysis using two control parameters that maps out periodic, period-multiplication, and chaotic regimes over a wide range of the input voltage and gas flow rate. In addition, optical emission signatures of excited plasma species are used as the second and independent observable to demonstrate the presence of chaos and period-doubling in both the concentrations and composition of plasma species, suggesting a similar array of periodic, quasi-periodic and chaotic regimes in plasma chemistry. The presence of quasi-periodic and chaotic regimes in structurally unbounded low-temperature atmospheric plasmas not only is important as a fundamental scientific topic but also has interesting implications for their numerous applications. Chaos may be undesirable for industrial applications where cycle-tocycle reproducibility is important, yet for treatment of cell-containing materials including living tissues it may offer a novel route to combat some of the major challenges in medicine such as drug resistance. Chaos in low-temperature atmospheric plasmas and its effective control are likely to open up new vistas for medical technologies.2

A Practical Method for Controlling the Asymmetric Mode of Atmospheric Dielectric Barrier Discharges

“…electron cited from [25] and i  is its mean energy; σs represents the surface charge density on the wall, and Je and Ji respectively denote the electron density and the ion density there; D1 and D2 are the electric displacement vectors on both sides of the interface; αs is a switching function as given below. (12) Here, q represents the signed charge. For chemical kinetics, we reused ones from our previous work [19].…”

“…However, under certain conditions, a lot of simulation and experimental research has reported that DBDs can also work in various nonlinear modes such as asymmetric period-one (henceforth called AP1), multi-period, quasi-period and chaos through different evolution routes [8][9][10][11]. Since different discharge modes can influence the stability of DBDs in terms of the density and composition of active species in discharge plasmas and then impact their efficacy in related applications [12,13], the investigation on the control of nonlinear modes is valuable and imperative both in theoretical and practical aspects. It is worth noting that before bifurcating into other nonlinear modes from SP1, the discharge always first transforms into the asymmetric mode as a transition phase [14].…”

Simulation study of one-dimensional self-organized pattern in an atmospheric-pressure dielectric barrier discharge

“…Clearly, in each position, the current amplitudes fluctuate stochastically with time, which is identical with the temporal chaos observed previously. [4][5][6][7][8] Taking the five-channels pattern for example, we study the formation process of pattern. Figures 11 and 12 present the temporal evolutions of electron density and surface charge density along y-direction including 30 periods.…”

“…31. The calculated u h and u l are substituted into the boundary condition (8) and (9). Using the above boundary conditions of Eqs.…”

The transition mechanism from a symmetric single period discharge to a period-doubling discharge in atmospheric helium dielectric-barrier discharge

“…[10][11][12] Recently, more complex temporal nonlinear behaviors of APGD, such as period-doubling bifurcation and chaos, have been frequently observed in both experiments and numerical simulations. [13][14][15][16][17][18][19] Different from the single period discharge, the current pulses in period-doubling and chaos discharges repeat at multiple applied voltage cycles or fluctuate stochastically. These nonlinear behaviors are sensitive to discharge parameters and can be caused by the fluctuations of a variety of control parameters, such as the driving frequency, voltage amplitude, and gap width.…”