Spatial Distribution of the Wave Field of Filamented High‐Frequency Discharges

Lishev, St.; Schlüter, H.; Shivarova, A.; Tarnev, Kh.

doi:10.1002/ppap.200500097

Plasma Processes & Polymers

2006

DOI: 10.1002/ppap.200500097

|View full text |Cite

Spatial Distribution of the Wave Field of Filamented High‐Frequency Discharges

St. Lishev

H. Schlüter

A. Shivarova

et al.

Abstract: Summary: This study is on high pressure surface wave‐sustained discharges at the stage of their contraction into filaments: gas discharge channels positioned in the off‐center region of the cross section of the discharge and extended along its length. Based on results for the dispersion behavior and the space distribution of the wave field, obtained by a 2D numerical code developed for describing surface wave properties in plasma with an arbitrary distribution of density, the structure of the modes sustaining … Show more

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...

Citation Types

Supporting

Mentioning

Contrasting

Year Published

2008

Publication Types

Select...

Article2

Relationship

Self Cite0

Independent2

Authors

Journals

Cited by 2 publications

(1 citation statement)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These few filaments are gas-discharge channels extending along the gas-discharge tube and positioned in the out-of-center region of its cross section, equidistantly in the azimuthal direction. The contraction of the discharge poses the question about the kind of surface modes guided by such a filamentary structure and the spatial distribution of their wave field, a problem that has been treated recently [4], [5] by covering not only plasma filaments but also the other plasma structures (plasma rings and dipole structures) which appear [1] at the different stages of the discharge contraction.…”

mentioning

confidence: 99%

Eigen Surface Modes of Filamentary Plasma Structures

Lishev

Shivarova

Tarnev

2008

IEEE Trans. Plasma Sci.

View full text Add to dashboard Cite

Calculated spatial distributions of the eigen surface modes guided by free-localized filamentary plasmas are presented. The plasma structures considered are those of surface-wavesustained discharges in the gas pressure range between 10 and 200 torr. Index Terms-Filamentary plasma structures, surface waves, surface-wave-sustained discharges.A S THE experiments [1] show, the self-organization of surface-wave-sustained discharges in the gas pressure range between diffusion-controlled discharges [2] and atmospheric-pressure discharges [3] results in their contraction into free-localized plasma structures of the filament type. These few filaments are gas-discharge channels extending along the gas-discharge tube and positioned in the out-of-center region of its cross section, equidistantly in the azimuthal direction. The contraction of the discharge poses the question about the kind of surface modes guided by such a filamentary structure and the spatial distribution of their wave field, a problem that has been treated recently [4], [5] by covering not only plasma filaments but also the other plasma structures (plasma rings and dipole structures) which appear [1] at the different stages of the discharge contraction.The current study is completely focused on the discharge contraction into filamentary structures and presents computationally generated images of the electromagnetic field configuration of the surface waves guided by such type of plasma structures.The results ( Fig. 1) presented here are obtained by employing the 2-D model developed in [5] for the description of the spatial distribution of the surface wave field in plasmas with an arbitrary (given) distribution of plasma density over the discharge cross section. The gas-discharge conditions chosen are as follows: a microwave (f ≡ ω/2π = 2.45 GHz) argon discharge at gas pressure p = 20 torr with a fixed ratio ν/ω = 0.25, where ω and ν are, respectively, the wave frequency and the elastic electron-neutral collision frequency for momentum transfer. The filamentary structure considered consists of 4 filaments as shown in Fig. 1. The filaments extend along the Manuscript discharge length, in the z-direction. In the cross section of the discharge [the (x−y)-plane in Fig. 1] a Gaussian distribution of the plasma density in each filament is assumed according to the experimental results in [6]. The positions of the center of the filaments and their width (being the same for all of them) are also according to the experiments [1]: filaments with a diameter of 4 mm located within a radius of 1 cm. The filaments are completely isolated from each other: Even the low-plasmadensity contours n e = 0.01n cr (where n cr is the usual critical density) close on themselves around each filament (Fig. 1).The spatial distribution of the wave-field components shown in Fig. 1 is obtained as a numerical solution of the wave equations written for the axial electric (E z ) and magnetic (H z ) field components. The two-dimensional variation of the plasma density-the azimuthal one in addit...

show abstract

mentioning

confidence: 99%

Eigen Surface Modes of Filamentary Plasma Structures

Lishev

Shivarova

Tarnev

2008

IEEE Trans. Plasma Sci.

View full text Add to dashboard Cite

show abstract

Spatial distribution of the wave field of the surface modes sustaining filamentary discharges

Lishev

Shivarova

Tarnev

2008

Journal of Applied Physics

View full text Add to dashboard Cite

The study presents the electrodynamical description of surface-wave-sustained discharges contracted in filamentary structures. The results are for the spatial distribution of the wave field and for the wave propagation characteristics obtained from a two-dimensional model developed for describing surface-wave behavior in plasmas with an arbitrary distribution of the plasma density. In accordance with the experimental observations of filamentary discharges, the plasma density distribution considered is completed by cylindrically shaped gas-discharge channels extended along the discharge length and positioned in the out-of-center region of the discharge, equidistantly in an azimuthal direction. Due to the two-dimensional inhomogeneity of the plasma density of the filamentary structure, the eigen surface mode of the structure is a hybrid wave, with all—six—field components. For identification of its behavior, the surface wave properties in the limiting cases of a plasma ring and a single filament—both radially inhomogeneous—are involved in the discussions. The presentation of the results is for filamentary structures with a decreasing number of filaments (from 10 to 2) starting with the plasma ring, the latter supporting propagation of an azimuthally symmetric wave. Due to the resonance absorption of the surface waves, always present because of the smooth variation of the plasma density, the contours of the critical density are those guiding the surface wave propagation. Decreasing number of filaments in the structure leads to localization of the amplitudes of the wave-field components around the filaments. By analogy with the spatial distribution of the wave field in the plasma ring, the strong resonance enhancement of the wave-field components is along that part of the contour of the critical density which is far off the center of the filamentary structure. The analysis of the spatial distribution of the field components of the filamentary structure shows that the hybrid wave is an eigenmode of the whole structure, i.e., the wave field does not appear as a superposition of fields of eigenmodes of the separated filaments completing it. It is stressed that the spatial distribution of the field components of the eigen hybrid mode of the filamentary structure has an azimuthally symmetric background field.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

hi@scite.ai

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Spatial Distribution of the Wave Field of Filamented High‐Frequency Discharges

Cited by 2 publications

References 13 publications

Eigen Surface Modes of Filamentary Plasma Structures

Eigen Surface Modes of Filamentary Plasma Structures

Spatial distribution of the wave field of the surface modes sustaining filamentary discharges

Contact Info

Product

Resources

About