A5010586738- Plasma Diagnostics and Applications
- Particle accelerators and beam dynamics
- Electrohydrodynamics and Fluid Dynamics
- Ion-surface interactions and analysis
- Laser-induced spectroscopy and plasma
- Metal and Thin Film Mechanics
- Magnetic confinement fusion research
- Radiation Effects in Electronics
- Advanced Data Storage Technologies
- Muon and positron interactions and applications
- Mass Spectrometry Techniques and Applications
- Rocket and propulsion systems research
- Nuclear Physics and Applications
- Dust and Plasma Wave Phenomena
- Cryptographic Implementations and Security
- Visual perception and processing mechanisms
- Copper Interconnects and Reliability
- Integrated Circuits and Semiconductor Failure Analysis
- Spacecraft and Cryogenic Technologies
- Astro and Planetary Science
- Atomic and Molecular Physics
- Energetic Materials and Combustion
- Vacuum and Plasma Arcs
- Electrostatic Discharge in Electronics
- Plasma Applications and Diagnostics
ThrustMe (France)
2018-2023
Laboratoire de Physique des Plasmas
2012-2017
Sorbonne Université
2014-2017
Centre National de la Recherche Scientifique
2013-2017
Université Paris-Saclay
2017
Université Paris Sciences et Lettres
2017
Université Paris-Sud
2017
École Polytechnique
2013-2017
Ministry of Education and Science
2011
V. N. Karazin Kharkiv National University
2009-2010
Propulsion is a critical subsystem of many spacecraft1-4. For efficient propellant usage, electric propulsion systems based on the electrostatic acceleration ions formed during electron impact ionization gas are particularly attractive5,6. At present, xenon used almost exclusively as an ionizable for space propulsion2-5. However, rare, it must be stored under high pressure and commercial production expensive7-9. Here we demonstrate system that uses iodine present in-orbit results this new...
The plasma propulsion with electronegative gases (PEGASES) thruster is a gridded ion that accelerates alternately positively and negatively charged ions to provide thrust. Over the last few years, various prototypes have been tested, adequate diagnostics developed, analytical models simulations are made better understand control physics involved. Here, we present state-of-the-art in PEGASES development as of 2013, discuss its possible future space.
Electric space propulsion is an intensively developing field addressing new demands and challenges for long-term spacecraft operation. Many novel plasma concepts aim to find acceleration principles, use alternative propellants, upscale or downscale thrusters large thrust very small spacecrafts etc. In this work we review the neutralizer-free concepts, where both positive negative particles are extracted accelerated from plasmas. We can divide these into three main categories, defined by...
Abstract Iodine is emerging as an attractive alternative propellant to xenon for several electric propulsion technologies due its significantly lower cost and ability be stored unpressurized a solid. Because of the more complex reaction processes energy-loss channels in iodine plasmas however, well historical lack reliable collision cross-section data, development accurate theoretical numerical models has been hindered. Using recently calculated cross-sections, we present plasma model...
The PEGASES (Plasma Propulsion with Electronegative Gases) thruster is a gridded ion thruster, where both positive and negative ions are accelerated to generate thrust. In this way, additional downstream neutralization by electrons redundant. To achieve this, the accelerates alternately from an ion-ion plasma electron density three orders of magnitude lower than densities. This paper presents first experimental study alternate acceleration in PEGASES, SF6 used as working gas. Various...
By applying a square-wave voltage with frequencies between 10 kHz to 1 MHz set of grids terminating an ion–ion plasma source, we experimentally demonstrate the alternate extraction and acceleration high energy (hundreds eV) positive negative ion beams. In addition, ratio positive-to-negative beam current can be controlled by adjusting applied duty cycle. Temporally resolved floating potential measurements target show that downstream sufficiently reduced at (∼200 kHz), indicating space-charge...
The results of investigations on the simultaneous extraction positive ions and electrons from a single-grid ICP source are reported. It is shown that ion capable generating coincident electron flows in contrast to more common two- or three-grid sources. Electron emission characteristics presented for cases DC RF acceleration bias. A method ion/electron current ratio control proposed allowing change compensation state beam non-compensated highly over-compensated. researches were conducted...
We propose an alternative method to accelerate ions in classical gridded ion thrusters and sources such that co-extracted electrons from the source may provide beam space charge neutralization. In this way there is no need for additional electron neutralizer. The consists of applying RF voltage a two-grid acceleration system via blocking capacitor. Due unequal effective area two grids contact with plasma, dc self-bias formed, rectifying applied voltage. As result, are continuously...
The extraction and acceleration of ions from a plasma source is often performed electrostatically using set direct-current (DC) biased grids. To ensure that equal currents positive negative charges are ejected, to compensate the downstream ion beam space charge, separate electron-emitting neutraliser required. If instead grids with radio-frequency (RF) voltage, then both electrons can be extracted same no longer needed. Using combination theory particle-in-cell simulations, we demonstrate...
In this work plasma acceleration using a RF self-bias effect is experimentally studied. The experiments are conducted novel accelerator system, called Neptune, consisting of an inductively coupled source and RF-biased set grids. can operate in steady state mode, producing flow with separately controlled flux velocity without any magnetic configuration. operating pressure at the output as low 0.2 mTorr further be decreased. ion electron flows investigated by measuring energy distribution...
This paper presents the development of a magnetized retarding field energy analyzer (MRFEA) used for positive and negative ion analysis. The two-stage combines magnetic electron barrier an electrostatic allowing both ions to be analyzed without influence electrons (co-extracted or created downstream). An optimal design MRFEA ion-ion beams has been achieved by comparative study three different configurations, from this, scaling laws strength topology have deduced. consists uniform in...
A 25 cm single-grid low-energy rf ion source with inherent electron compensation is described and characterized. Measurements were carried out using Ar CF4 filling gas. The dependence of the beam current to target as well partition between fast slow ions on discharge pressure for both gases discussed. unique ability generation coinciding flows demonstrated measured energy distribution functions are presented well. developed broad able providing 0.5–5 mA/cm2 density in low range 50–250 eV,...
The present research is devoted to the problem of extraction grid choice for a single-grid source bipolar ion-electron flow. paper contains detailed reference information on ion and electron characteristics 10 different grids with broad range parameters: aperture width (0.09-0.6 mm), transparency (0.19-0.51), thickness (0.036-0.5 geometry. square, circular, slit apertures were made technologies: laser cutting, welding, weaving, electrolytic erosion. general regularities from are...
Abstract Electrons neutralizing the ion beam from a gridded source are typically provided by an external cathode. This cathode emits continuous current that ensures quasi-neutrality of plume, and balance source. A new type neutralization scheme has recently been identified in context radio-frequency (RF) biased sources, where instead electron current, plume is neutralized pulses emitted same plasma as itself. In contrast to conventional experiments have shown pulsed produces hot electrons...
A new system providing continuous generation of broad negative-ion beam is described and characterized. The key element the grid-type electron filter allowing formation without magnetic field a stationary highly electronegative plasma which can be biased negatively with respect to relatively high-area electrode that allows extract negative ions. Measurements energy distribution functions conducted using magnetically filtered analyzer show (250 mm) controllable starting from several eV....
This paper presents experimental results showing that continuous negative ion extraction, without co-extracted electrons, is possible from highly electronegative SF6 ion-ion plasma at low gas pressure (1 mTorr). The ratio between the and electron densities more than 3000 in vicinity of two-grid extraction acceleration system. measurements are conducted by both magnetized non-magnetized energy analyzers attached to external grid. With these two analyzers, we show extracted flux almost...
An automated plume diagnostic system is presented for two-dimensional mapping of the ion beam produced by using miniaturized electric propulsion devices. The instrument designed to operate with noble and reactive gases consists a semi-circular probe array unique angular distribution following Gaussian shape improved profile resolution. To demonstrate operation system, series experiments are conducted low-power gridded thruster xenon iodine propellants. current density maps generated used...
Flowing plasmas are of significant interest due to their role in astrophysical phenomena and potential applications magnetic-confined fusion spacecraft propulsion. The acceleration a charge-neutral plasma beam using the radio-frequency self-bias concept could be particularly useful for development neutralizer-free propulsion sources. However, mechanisms that lead space-charge compensation exhaust unclear. Here, we spatially temporally resolve propagation electrons an accelerated is generated...
A double-plasma source capable of the generation a continuous bipolar ion-ion beam is described. The quasi-neutral flow to an extraction electrode formed in system containing primary inductively coupled plasma separated from secondary by electrostatic grid-type filter. total current each ion species 250 mm diameter about 80 mA; electron does not exceed 30% current. Method positive/negative ratio control proposed, allowing currents variation wide range.
In this paper, a diagnostic method for magnetized and unmagnetized laboratory plasma is proposed, based on impedance measurements of short matched dipole. The range the measured electron densities limited to low density plasmas (1012–1015 m−3), where other methods have strong limitations magnetic field strength topology, dimensions, boundary conditions. designed use in both large- small-dimension (<10 cm) without or with non-homogeneous field, which can be undefined within probe size....
In this paper, the PEGASES II thruster prototype is used as an ion source generating low-energy positive Ar beam, extracted without external neutralizer. The ions are and accelerated from using a two-grid system. beam current measured on large target that can be translated along acceleration axis. shows stepwise transition low-current to high-current extraction regime with hysteresis. hysteresis region depends strongly upon position. Langmuir probe measurements in plume show high plasma...
In the present paper, deposition processes and formation of films in SF6 ion-ion plasma, with positive negative ion flows accelerated to surface, are investigated. The PEGASES (acronym for Plasma Propulsion Electronegative GASES) source is used as an plasma capable generating almost ideal electron density ratio more than 2500. It shown that film very sensitive polarity incoming ions. effect observed Cu, W, Pt materials. formed on Cu electrodes during assisted were analyzed. Scanning...
PEGASES is a gridded ion thruster that accelerates both positively and negatively charged ions for thrust. Halogen contained gases are used as propellant to create the two types of ions. The particle transport within plasma source controlled by localized magnetic field such region described an ion-ion formed in front acceleration grids. grid system consists or more grids, where first contact with biased square voltage waveforms. positive negative accelerated across grids respective...