Filamentary streamer discharges in argon at atmospheric pressure excited by surface plasmon polaritons

Abstract

This paper describes a microwave plasma jet in an argon atmosphere capable of generating filamentary streamer discharges within the entire quartz tube excited by surface waves of surface plasmon polaritons (SPPs) located in the tube. Several discharge streamers are immediately produced at the end of the copper wire when incident power reaches 20 W. From simulations, the wavelength of the surface wave was found to be approximately 5.7 cm. Although the developing streamers induce E-field enhancements favoring discharging, more streamer bifurcations requiring additional energy to maintain discharging diminish the resonant enhanced E-field. The underlying mechanism of the proposed plasma jet is resonant excitation of SPPs and its interaction with plasmas.

Self-consistent fluid modeling and simulation on a pulsed microwave atmospheric-pressure argon plasma jet

“…Thence, the bulk plasma density n bulk can be calculated 8:3 Â 10 20 m -3 approximately. It should be mentioned that although this density value is consistent with previous studies reported from the similar lowerpower argon microwave plasma jets driven by continues microwave power in ambient air, [3][4][5][6][7][8][9][10][11][12][13][14][15][16]32 the actual plasma density of the pulsed plasma jet is lower than this value, due to the average power absorbed by the electrons lower largely in pulsed discharge with the same peak power amplitude.…”

“…According to Eqs. (5) and (18) electron density and also square proportional to the electric field. Thence, although the electron density peaks at 25 ls, the absorbed power density gets its maximum value at 12 ls, due to the peak electric field occurring at 10 ls.…”

“…The electric field of SPPs enhances largely at the interface. On the dielectric-metal interface, the propagation constant k spp is given by 5,[29][30][31] …”

“…[29][30][31] At dielectric-metal interfaces, a remarkably enhanced near-field is resulted in through the resonant interaction between the SPPs and the EM radiation and meanwhile the effective discharge with lower applied power is induced. 5 be the only method to obtain more accurate information of the ionizing process, step by step in detail.…”

“…1,2 One type of them, named low-power microwave-driven atmospheric plasma jet, is generated based on microwave resonant effect, which have several advantages over low-frequency plasmas, such as higher density of electron and reactive species, lower plasma plume temperature, lower applied power, and longer electrode lifetime. [3][4][5][6][7] Especially for several applications, such as medical instrument sterilization, metal surface nitriding, and high-velocity fuel ignition and combustion, atmospheric microwave plasma devices have shown its potential advantages in industrial applications. [8][9][10][11] There are four types of low-power microwave resonators: coaxial transmission line resonators (CTLR), 3 microstrip line resonators, 4 surfatron launchers, 12 and surface-wave plasma jets, [13][14][15] which are with different characteristics and thereafter are constructed for satisfying different application demands.…”