Electron hole and electron wave excitation in a plasma with transverse effects

1986 ◽  
Vol 36 (3) ◽  
pp. 453-463 ◽  
Author(s):  
Satoru Iizuka ◽  
Hiroshi Tanaca
Keyword(s):  
Plasma Source ◽  
Plasma Potential ◽  
Particle Model ◽  
Wave Excitation ◽  
Electron Wave ◽  
Qualitative Properties ◽  
Electron Hole ◽  
The Poisson Equation ◽  
Electron Holes ◽  
Good Agreement

Excitation of electron holes and electron wave pulses is investigated numerically in a single-ended plasma by computer simulation using a particle model. The transverse effects are taken into account by introducing the perpendicular wavenumber in the Poisson equation. Increase in the plasma potential in front of a plasma source, resulting from propagation of the rarefaction pulse from an end boundary, gives rise to the excitation of electron holes, while the rarefaction pulse reflects back as the compression pulse toward the boundary. The qualitative properties are in good agreement with experiment.

An Analytical Drain Current Model for Dual-material Gate Graded - channel and Dual-oxide Thickness Cylindrical Gate (DMG-GC-DOT) MOSFET

2019 ◽  
Vol 9 (2) ◽  
pp. 291-297
Author(s):  
Hind Jaafar ◽  
Abdellah Aouaj ◽  
Ahmed Bouziane ◽  
Benjamin Iñiguez
Keyword(s):  
Current Model ◽  
Drain Current ◽  
Oxide Thickness ◽  
Subthreshold Current ◽  
The Poisson Equation ◽  
Strong Inversion ◽  
Cylindrical Form ◽  
Silvaco Atlas ◽  
Dual Material ◽  
Good Agreement

Background: A novel Dual Material Gate Graded Channel and Dual Oxide Thickness Cylindrical Gate (DMG-GC-DOT) MOSFET is presented in this paper. Methods: Analytical model of drain current is developed using a quasi-two-dimensional cylindrical form of the Poisson equation and is expressed as a function of the surface potential, which is calculated using the expressions of the current density. Results: Comparison of the analytical results with 3D numerical simulations using Silvaco Atlas - TCAD software presents a good agreement from subthreshold to strong inversion regime and for different bias voltages. Conclusion: Two oxide thicknesses with different permittivity can effectively improve the subthreshold current of DMG-GC-DOT MOSFET.

Nonlinear electron-wave excitation in microwave Cherenkov's devices

1997 ◽  
Author(s):  
Viktor M. Pikunov ◽  
Igor A. Chernyavskiy
Keyword(s):  
Wave Excitation ◽  
Electron Wave

scholarly journals Measured Stark widths and shifts in the O IV spectrum

2003 ◽  
pp. 51-54 ◽  
Author(s):  
Stevan Djenize ◽  
Aleksandar Sreckovic ◽  
Srdjan Bukvic ◽  
Slobodanka Kalezic
Keyword(s):  
Arc Discharge ◽  
Theoretical Data ◽  
Plasma Source ◽  
Spectral Lines ◽  
Pulsed Arc Discharge ◽  
D Values ◽  
And Shifts ◽  
Pulsed Arc ◽  
Good Agreement ◽  
Thin Plasma

Stark widths (W) and shifts (d) of 5 prominent triply ionized oxygen (O IV) spectral lines in 3 multiplets have been measured in oxygen plasma at 42 000 K electron temperature using a linear, low-pressure, pulsed arc discharge as an optically thin plasma source. Obtained W and d values have been compared to available experimental and theoretical data. We found a good agreement among our experimental W and d values and theoretical expectations.

scholarly journals Effect of permanent magnets on plasma confinement and ion beam properties in a double layer helicon plasma source

2019 ◽  
Vol 85 (3) ◽  
Author(s):  
Erik Varberg ◽  
Åshild Fredriksen
Keyword(s):  
Magnetic Field ◽  
Permanent Magnets ◽  
Ion Beam ◽  
Plasma Source ◽  
Diffusion Chamber ◽  
Plasma Potential ◽  
Field Energy ◽  
Plasma Confinement ◽  
Plasma Device ◽  
Field Lines

The work described in this article was carried out to investigate how permanent magnets (PM) affect the plasma confinement and ion beam properties in an inductively coupled plasma which expands from a helicon source. The cylindrical plasma device Njord has a 13 cm long and 20 cm wide stainless steel port connecting the source chamber and the diffusion chamber. The source chamber has an axial magnetic field produced by two coils, with magnetic field lines expanding into the diffusion chamber. Simulations have shown that the field lines leaving the edge of the source hit the port wall, causing a loss of electrons in this section. In the experiments performed in this work, PMs were added around the port walls near the exit of a plasma source and the effect was investigated experimentally by means of a retarding field energy analyser probe. The plasma potential, ion density and ion beam parameters were estimated, and the results with and without the PMs were compared. The results showed that the plasma density in the centre can in some cases be doubled, and the density at the edges of the plasma increased significantly with PMs in place. Although the plasma potential was slightly affected, and the beam velocity dropped by ${\sim}$ 10 %, the ion beam flux increased by a factor of 1.5.

scholarly journals Effect of Magnetic Field on Dilepton Production Rate in Relativistic Heavy Ion Collisions

2020 ◽  
Vol 12 (2) ◽  
pp. 215-221
Author(s):  
P. K. Sethy ◽  
Y. Kumar ◽  
S. S. Singh
Keyword(s):  
Magnetic Field ◽  
Heavy Ion ◽  
Relativistic Heavy Ion Collisions ◽  
Particle Model ◽  
Heavy Ion Collision ◽  
Dilepton Production ◽  
Quasi Particle ◽  
Ion Collisions ◽  
Ion Collision ◽  
Good Agreement

It is believed that a transient strong magnetic field is generated in heavy-ion collision. The strength of this field perpendicular to the reaction plane and is estimated to be around eB=0.03GeV2 at RHIC and eB=0.3GeV2 at LHC. We study the effect of this magnetic field on dilepton yield using a modified quasi particle model. The results show a clear enhancement in dilepton yield and our result is in good agreement with the recently reported results.

Electron holes in the Earth's magnetotail current sheet: role of magnetic field gradients and electron anisotropy

2020 ◽  
Author(s):  
Pavel Shustov ◽  
Ilya Kuzichev ◽  
Ivan Vasko ◽  
Anton Artemyev ◽  
Anatoliy Petrukovich
Keyword(s):  
Magnetic Field ◽  
Current Sheet ◽  
Magnetic Field Gradient ◽  
Electron Distribution Function ◽  
Inhomogeneous Magnetic Field ◽  
Field Configuration ◽  
Slow Electron ◽  
Electron Hole ◽  
Field Lines ◽  
Electron Holes

<p>Electron holes are nonlinear electrostatic structures that are often observed in the vicinity of the magnetotail energy release regions, e.g. magnetic reconnection. In this work we develop 1.5D Vlasov code simulations of the electron hole dynamics in the magnetic field configuration typical of the current sheet of the Earth's magnetotail. We consider the propagation of electron holes along magnetic field lines in the inhomogeneous magnetic field of the current sheet with realistically anisotropic electron distribution function. We demonstrate that electron holes generated near the equatorial plane of the current sheet brake as they propagate toward the boundaries of the current sheets. This effect is stronger for higher magnetic field gradient and larger electron field-aligned anisotropy. These simulations demonstrate that slow electron holes observed in the plasma sheet boundary layer may appear due to that effect of electron hole braking.</p>

scholarly journals Walking Around Ribosomal Small Subunit: A Possible “Tourist Map” for an Electron Hole

2021 ◽  
Author(s):  
Andrey Yu. Sosorev
Keyword(s):  
Protein Synthesis ◽  
Small Subunit ◽  
The Body ◽  
Translation Process ◽  
Electron Hole ◽  
Rna Molecules ◽  
Charge Localization ◽  
Allosteric Mechanism ◽  
Electron Holes ◽  
Hole Localization

Despite several decades of research, the physics underlying translation – protein synthesis at the ribosome – remains poorly studied. For instance, the mechanism coordinating various events occurring in distant parts of the ribosome is unknown. Very recently, we have suggested that this allosteric mechanism could be based on the transport of electric charges (electron holes) along RNA molecules and localization of these charges in the functionally important areas; this assumption was justified using tRNA as an example. In this study, we turn to the ribosome and show computationally that holes can also efficiently migrate within the whole ribosomal small subunit (SSU). The potential sites of charge localization in SSU are revealed, and it is shown that most of them are located in the functionally important areas of the ribosome – intersubunit bridges, Fe4S4 cluster and the pivot linking the SSU head to the body. As a result, we suppose that hole localization within the SSU can affect intersubunit rotation (ratcheting) and SSU head swiveling, in agreement with the scenario of electronic coordination of ribosome operation. We anticipate that our findings will improve the understanding of the translation process and advance the molecular biology and medicine.

scholarly journals Measurement of Plasma Potential, Ion Saturation Current and Mach number using Retarding Field Energy Analyzer

2021 ◽  
Vol 7 (2) ◽  
pp. 76-80
Author(s):  
L. N. Mishra ◽  
Å. Fredriksen
Keyword(s):  
Mach Number ◽  
Plasma Source ◽  
Diffusion Chamber ◽  
Plasma Potential ◽  
Field Energy ◽  
Saturation Current ◽  
Energy Analyzer ◽  
Temperature Plasma ◽  
Helicon Plasma ◽  
Side Walls

This article deals about the experimental measurement of plasma potential, ion saturation current and Mach number obtained with the variation of power, operating gas pressure and radial position using retarding field energy analyzer. We employed a retarding field energy analyzer by rotating with different angles such as 0° (facing toward source), 90° (facing side walls) and 180° (facing opposite the source). The coil current is varied from 0 to 15 A to produce the magnetic field which is used to confine the plasma. The flow of plasma has been characterized which was found to be subsonic. The low-temperature plasma is produced by means of a 13.56 MHz helicon plasma source at 300-1000 kW radio frequency power. The plasma is expanding from 13.8 cm diameter source into a 150 cm long diffusion chamber of 60 cm diameter.

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