Spatially resolved determination of the electronic density and temperature by a visible spectro-tomography diagnostic in a linear magnetized plasma

Gonzalez-Fernandez, V.; David, P.; Baude, Romain; Escarguel, A.; Camenen, Y.

doi:10.1038/s41598-020-62426-9

Cited by 13 publications

(3 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…other typical E × B plasmas, such as Hall thrusters [9][10][11][12][13] and Penning discharges [14][15][16][17]. The spoke significantly affects the dynamics of electrons and ions and its fundamental understanding is hereby of importance in the operation and control of these E × B plasma based applications [15,[18][19][20][21][22][23][24][25][26][27].…”

Section: Introductionmentioning

confidence: 99%

Rotating spokes, potential hump and modulated ionization in radio frequency magnetron discharges

Xu,

Sun,

Eremin

et al. 2023

Plasma Sources Sci. Technol.

View full text Add to dashboard Cite

In this work, the transition from the gradient drift instability (GDI) into an m = 1 rotating spoke in the radio frequency magnetron discharge was studied by means of the two-dimensional axial-azimuthal (z − y) particle-in-cell/Monte Carlo collision method. The kinetic model combined with the linear analysis of the perturbation revealed that the cathode sheath (axial) electric field E z triggers the GDI, deforming the local potential until the instability condition is not fulfilled and the fluctuation growth stops in which moment the instability becomes saturated. The potential deformation consequently leads to the formation of the potential hump, surrounding which the azimuthal electric field E y is present. The saturation level of E y was found to be synchronized with and proportional to the time-changing voltage applied at the cathode, resulting in the RF-modulation of the electron heating in the E y due to ∇ B drift. In the saturated stage of the instability, it was shown that the rotation velocity and direction of the spoke present in the simulations agree well with the experimental observation (Panjan 2019 J. Appl. Phys. 125 203303). In the instability linear stage, the instability mode wavelength and the growth rate were also found to be in good agreement with the prediction of the GDI linear fluid theory.

show abstract

Section: Introductionmentioning

confidence: 99%

Rotating spokes, potential hump and modulated ionization in radio frequency magnetron discharges

Xu,

Sun,

Eremin

et al. 2023

Plasma Sources Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…A particular physics device is really required to be constructed for the future development of plasma physics, although physics experiments conducted in rather low-temperature devices have become a new international trend. 125 – 128 ) The PLATO device, a tokamak with tomography, is constructed exactly for the purpose to realize measurements covering the entire field of plasma turbulence so as to pursue the reality of turbulent plasma. The research of turbulent plasma provides a new physics field for the 21st century, that is, as a representative system of far non-equilibrium and strong nonlinearity, as well as contributing to realizing an economic nuclear fusion reactor.…”

Section: Future Prospects and Conclusionmentioning

confidence: 99%

Review of plasma turbulence experiments

Fujisawa

2021

Proceedings of the Japan Academy. Ser. B: Physical and Biologic

View full text Add to dashboard Cite

Understandings of turbulent plasma have been developed along with nuclear fusion research for more than a half century. Long international research has produced discoveries concerning turbulent plasma that allow us to notice the hidden nature and physics questions that could contribute to other scientific fields and the development of technologies. Guiding concepts have been established up to now that stimulate investigations on turbulent plasma. Research based on concepts concerning symmetry breaking and global linkage requires observing the entire field of plasma turbulence for an ultimate understanding of plasma. This article reviews the achievements as well as contemporary problems regarding turbulence experiments associated with strongly magnetized plasmas in the last and present century, and introduces forthcoming experimental issues, including new diagnostics and physics-oriented devices related to plasma turbulence.

show abstract

“…In the latter examples, the light intensity is usually considered as a proxy for the ion saturation current, or for the density, with correlations up to 0.75 26 . In low temperature and weakly ionized plasma, this approximation is usually by the Corona model [27][28][29] which assumes that the main source for photons emission is radiative decay from excited states that are populated by electronic collisions from the ground state. As a consequence the intensity of the light emitted by the radiative decay from the electronic level p to level k of a species α satisfies:…”

Section: Introductionmentioning

confidence: 99%

High-speed imaging of magnetized plasmas: when electron temperature matters

Vincent,

Dolique,

Plihon

2021

Preprint

View full text Add to dashboard Cite

High speed camera imaging is a powerful tool to probe the spatiotemporal features of unsteady processes in plasmas, usually assuming light fluctuations to be a proxy for the plasma density fluctuations. In this article, we systematically compare high speed camera imaging with simultaneous measurements of the plasma parameters -plasma density, electron temperature, floating potential -in a modestly magnetized Argon plasma column at low pressure (1 mTorr, magnetic fields ranging from 160 to 640 G). The light emission was filtered around 488 ± 5 nm, 750 ± 5 nm, 810 ± 5 nm. We show that the light intensity cannot be interpreted as a proxy for the plasma density and that the electron temperature cannot be ignored when interpreting high speed imaging, both for the time-averaged profiles and for the fluctuations. The features of plasma parameter fluctuations are investigated, with a focus on ion acoustic waves (at frequency around 70 kHz) at low magnetic field and low-frequency azimuthal waves (around a few kHz) at larger magnetic fields. An excellent match is found between the high speed images fluctuations and an Arrhenius law functional form which incorporates fluctuations of the plasma density and of the electron temperature. These results explain the discrepancies between ion saturation current and narrow-band imaging measurements previously reported in the literature.

show abstract

Spatially resolved determination of the electronic density and temperature by a visible spectro-tomography diagnostic in a linear magnetized plasma

Cited by 13 publications

References 22 publications

Rotating spokes, potential hump and modulated ionization in radio frequency magnetron discharges

Rotating spokes, potential hump and modulated ionization in radio frequency magnetron discharges

Review of plasma turbulence experiments

High-speed imaging of magnetized plasmas: when electron temperature matters

Contact Info

Product

Resources

About