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1.
Analysis of electron energy distribution function in a magnetically filtered complex plasma 下载免费PDF全文
The electron energy distribution function (EEDF) for a magnetically filtered dusty plasma is studied in a dusty double plasma device where the electron energy can be varied from 0.15 eV to ~ 2.8 eV and plasma density from 10 6 cm-3 to 10 9cm-3 . The characteristics of EEDF for these ranges of plasma parameters are investigated in a pristine plasma as well as in a dusty plasma. The results show that in the presence of dust, there is a drastic modification in EEDF patterns in a plasma with higher electron temperature and density than those in a low temperature and low density plasma produced by the magnetic filter. 相似文献
2.
The experimental observation of Peregrine solitons in a multicomponent plasma with the critical concentration of negative ions is reported. A slowly amplitude modulated perturbation undergoes self-modulation and gives rise to a high amplitude localized pulse. The measured amplitude of the Peregrine soliton is 3 times the nearby carrier wave amplitude, which agrees with the theory. The numerical solution of the nonlinear Schr?dinger equation is compared with the experimental results. 相似文献
3.
A.J. ChoudhuryS.A. Barve Joyanti Chutia A.R. PalR. Kishore JagannathM. Pande D.S. Patil 《Applied Surface Science》2011,257(20):8469-8477
Hexamethyldisiloxane (HMDSO) films have been deposited on bell metal using radiofrequency plasma assisted chemical vapor deposition (RF-PACVD) technique. The protective performances of the HMDSO films and their water repellency have been investigated as a function of DC self-bias voltage on the substrates during deposition. Plasma potential measurements during film deposition process are carried out by self-compensated emissive probe. Optical emission spectroscopy (OES) analyses of the plasma during deposition reveal no significant change in the plasma composition within the DC self-bias voltage range of −40 V to −160 V that is used. Raman and X-ray photoelectron spectroscopy (XPS) studies are carried out for film chemistry analysis and indicate that the impinging ion energy on the substrates influences the physio-chemical properties of the HMDSO films. At critical ion energy of 113 qV (corresponding to DC self-bias voltage of −100 V), the deposited HMDSO film exhibits least defective Si-O-Si chemical structure and highest inorganic character and this contributes to its best corrosion resistance behavior. The hardness and elastic modulus of the films are found to be bias dependent and are 1.27 GPa and 5.36 GPa for films deposited at −100 V. The critical load for delamination is also bias dependent and is 11 mN for this film. The water repellency of the HMDSO films is observed to be dependent on the variation in surface roughness. The results of the investigations suggest that HMDSO films deposited by RF-PACVD can be used as protective coatings on bell metal surfaces. 相似文献
4.
Considering the Boltzmann response of the plasma ions and electrons and inertial dynamics of the charged dust grains, the
possibility of very weak compressive soliton near the continuum limit of the dust population has been inferred. It is concluded
that the behaviour of such coherent structures could be well described by the numerical analysis of the derived nonlinear
classical energy integral equation for bounded solutions. These seem to be higher order dispersive structures within acoustic
limit of the nonlinear turbulence. It is observed that the dust density enhancement beyond the continuum threshold causes
regular increment in width and amplitude of the soliton structures. It is found that the soliton amplitude sensitively depends
on the massive impurity’s population. These coherent structures could be visualized as weakly charged solitary dust clouds
of finite extension (∼ plasma Debye length) within Boltzmann environment of plasma particles in their local surroundings.
The seeding mechanism of such clouds may be attributed to some plasma instabilities driven by either internal or external
free energy sources. Numerical analysis of the problem concludes that the experimental observations of such clouds could be
possible in low density plasma regime. It is deduced that for plasma density ∼ 106 cm-3 at temperatures of a few electron volts and for micron to l0nm sized dust grains, the observation of such structures could
be possible within wide range variability of the dust population density. 相似文献
5.
Nirab Chandra Adhikary Arup Ratan Pal Heremba Bailung Joyanti Chutia 《Physics letters. A》2006,350(5-6):380-385
In this Letter the long-range time correlations present in the fluctuation data in presence of electrostatic instability in a magnetised dc discharge plasma is presented. The electrostatic instability is generated due to the effect of crossed electric and magnetic field (E×B flow) and has intermediate frequency ranging from 50 to 100 MHz. Hurst exponent, the self-similarity parameter is calculated with the help of different statistical methods suggested by many researchers to determine the long-range time correlation present in fluctuation dynamics in the plasma column. The fluctuation in the ion saturation current is measured by a Langmuir probe for the study and the measurement is done both radially and axially in the plasma system. Estimated results clearly expose the self-similar character of the fluctuations with self-similarity parameters having values from 0.65 to 0.90 through the presence of long-range time correlation. 相似文献
6.
Bimal K. Sarma Arup R. Pal Heremba Bailung Joyanti Chutia 《Plasma Chemistry and Plasma Processing》2011,31(5):741-754
Plasma polymerization of aniline is carried out in a radiofrequency plasma reactor and the effect of polymerization time is
examined in the structural, optical and optoelectronic properties of deposited films. Conjugated structures of polyaniline
like films are obtained with unique and broad optical absorption band in the ultraviolet and entire visible region. The width
of the absorption band increases and hence the optical band gap decreases with polymerization time. The optical constants
are extracted by Swanepoel method and the optical dispersion parameters are determined by employing the Wemple-DiDomenico
single oscillator model. The films exhibit similar thermal stability in air and argon atmosphere in the region of interest
for optoelectronic applications. The photoluminescence study suggests, like the chemically synthesized polyaniline, the benzenoid
units to be responsible for fluorescence. The fluorescence peaks due to defect states confirm the formation of spectroscopic
units in the plasma polyaniline films. 相似文献
7.
Boruah Palash Jyoti Khanikar Rakesh Ruchel Bailung H. 《Plasma Chemistry and Plasma Processing》2020,40(4):1019-1036
Plasma Chemistry and Plasma Processing - Narrow bandgap tungsten oxide (WO3?x) nanoparticles have been synthesized by single-step plasma discharge in deionized water between two vertically... 相似文献
8.
Study of electron drift velocity caused by Etimes B motion is done with the help of a Mach probe in a dc cylindrical magnetron sputtering system at different plasma discharge parameters like discharge voltage, gas pressure and applied magnetic field strength. The interplay of the electron drift with the different discharge parameters has been investigated. Strong radial variation of the electron drift velocity is observed and is found to be maximum near the cathode and it decreases slowly with the increase of radial distance from the cathode. The sheath electric field, E measured experimentally from potential profile curve using an emissive probe is contributed to the observed radial variation of the electron drift velocity. The measured values of the drift velocities are also compared with the values from the conventional theory using the experimental values of electric and magnetic fields. This study of the drift velocity variation is helpful in providing a useful insight for determining the discharge conditions and parameters for sputter deposition of thin film. 相似文献
9.
Amreen A. Hussain Shyamalima Sharma Arup R. Pal Heremba Bailung Joyanti Chutia Dinkar S. Patil 《Plasma Chemistry and Plasma Processing》2012,32(4):817-832
The role of plasma parameters on the film characteristics is investigated on polyaniline thin film deposited by radio frequency (RF) plasma polymerization. A series of un-doped and iodine doped polyaniline thin films are prepared by RF discharge operating at 13.56?MHz with different discharge powers and pressure variation from 0.1 to 0.05?mbar and variation in deposition time from 20 to 40?min. A good thin film is found with a power ranging from 9?W (?28?V self bias) to 20?W (?65?V self bias) at 0.1?mbar pressure which is confirmed by fourier transform infra-red spectroscopy showing the retention of aromatic rings. In addition, iodine doping is carried out with 9?W power and 0.1?mbar pressure. The characterization of process plasma is done using Langmuir probe diagnostics and optical emission spectroscopy. A correlation has been established between film characteristics and plasma properties investigated using optical emission spectroscopy and Langmuir probe analysis. Emphasis has been given on the study of the influence of plasma parameters, particularly of the electron energy distribution function on the quality of conjugated plasma polymerized aniline film. 相似文献
10.
Properties of steady state ion sheath formed in front of a negatively biased metal plate under the influence of negative ions
have been investigated in collisionless argon/SF6 plasma. This experiment is carried out at a fixed discharge voltage and fixed filament heating power. In this experiment,
the decrement in plasma pre-sheath potential drop as well as positive ion drift velocity toward the plate is experimentally
recorded in the presence of negative ions. It is also found that the plasma positive ion density and plasma electron temperature
decrease in the presence of negative ions. These factors attribute to the decrease of ion current toward the plate. Hence
the usual ion sheath expands.
Article presented at the International Conference on the Frontiers of Plasma Physics and Technology, 9–14 December 2002, Bangalore,
India. 相似文献