Radio-Frequency Probes in a Nonlinear Isotropic Plasma

1974 ◽  
Vol 52 (4) ◽  
pp. 291-301 ◽  
Author(s):  
Colin C. Bantin ◽  
Keith G. Balmain
Keyword(s):  
Radio Frequency ◽  
Cold Plasma ◽  
Nonlinear Response ◽  
Plasma Frequency ◽  
Second Harmonic ◽  
Second Order ◽  
Constant Current ◽  
Constant Voltage ◽  
Isotropic Plasma ◽  
Input Signals

Nonlinear cold-plasma and scalar-pressure theories are derived and applied to a spherical RF probe in a plasma. With two specified RF potentials on the probe at different frequencies, calculations are presented for the second-order probe output responses. These include the second harmonic, the sum and difference frequencies, and the d.c. increment (resonance rectification). The nonlinear response as a function of frequency is shown to depend strongly on whether the input signals are maintained at a constant current or a constant voltage; for diagnostics, the constant-current technique permits identification of the plasma frequency, whereas the constant-voltage technique does not.

Small amplitude transverse wave propagation in a weakly Langmuir turbulent plasma

1969 ◽  
Vol 3 (4) ◽  
pp. 593-601
Author(s):  
N. Bel ◽  
J. Heynaerts
Keyword(s):  
High Frequency ◽  
Small Amplitude ◽  
Cold Plasma ◽  
Plasma Frequency ◽  
Turbulent Plasma ◽  
Distribution Functions ◽  
Isotropic Plasma ◽  
Particle Correlation ◽  
Special Cases ◽  
Corrective Term

The high frequency conductivity tensor of an isotropic plasma is derived taking into account particle correlations at the lowest consistent order in the parameter ωp/ω these correlations describe a weakly Langmuir turbulent plasma. Two special cases are investigated in which the two-particle correlation function is related to the turbulent electrostatic field spectrum. Particular distribution functions and spectra are considered and approximate dispersion relations are derived in both cases in ‘the cold plasma limit’. The importance of the corrective term is discussed in terms of three dimensionless parameters measuring the strength of the turbulence, the shape of the spectrum, and the frequency. The effect could be important for frequencies not too far from the plasma frequency.

Penetration to second order of an electrostatic field into a warm plasma

1971 ◽  
Vol 5 (1) ◽  
pp. 73-87
Author(s):  
E. M. Zawadzki ◽  
G. J. Lewak
Keyword(s):  
Plasma Frequency ◽  
Second Harmonic ◽  
Second Order ◽  
Electron Velocity ◽  
Electron Velocity Distribution ◽  
Electrostatic Waves ◽  
Harmonic Field ◽  
Warm Plasma ◽  
Boundary Fields ◽  
Vlasov Plasma

Using a reformulation of ordinary perturbation theory to first and second order, explicit solutions for the penetration of electrostatic waves into a semi-infinite Vlasov plasma are presented. Two types of electron velocity distribution are used, the uniform step (‘water-bag’ model) and the Maxwellian. The existence of propagating modes below the plasma frequency, behaviour of the second harmonic field and the formation of a narrow sheet of electrons near the bounding wall are displayed. Replacement of boundary fields with equivalent charge and current sources is discussed.

Tunable Second-Harmonic Studies of Gan Films Near the Fundamental Bandedge

1994 ◽  
Vol 339 ◽  
Author(s):  
Joseph Miragliotta ◽  
Wayne A. Bryden ◽  
Thomas J. Kistenmacher ◽  
Dennis K. Wickenden
Keyword(s):  
Photon Energy ◽  
Absorption Edge ◽  
Nonlinear Response ◽  
Second Harmonic ◽  
Wide Bandgap ◽  
Second Order ◽  
Nonlinear Susceptibility ◽  
Transmission Measurements

ABSTRACTTunable second-harmonic (SH) transmission measurements were performed on a series of GaN films epitaxially deposited onto (OOOl)-oriented sapphire. Analysis of the nonlinear response showed an increase in the second-order nonlinear susceptibility (χ(2)ijk) when the photon energy of the SH field was tuned above the absorption edge in each respective film. Specifically, the magnitude of the χ(2)zxx element in χ(2)ijk reached a maximum of 0.5 × 10-7 e.s.u. just above the the fundamental bandgap with a dispersion similar to the predicted nonlinear response in wide-bandgap cubic zincblende II-VI semiconductors such as ZnSe.

Second-order classical nonlinear response theory

AIAA Journal ◽  
2001 ◽  
Vol 39 ◽  
pp. 962-965
Author(s):  
Abdulmuhsen H. Ali
Keyword(s):  
Nonlinear Response ◽  
Second Order ◽  
Response Theory

HOMOGENITAS PRODUKSI BATERAI ION LITIUM BERDASARKAN VARIANS KAPASITAS PENGISIAN, KAPASITAS PELEPASAN DAN EFISIENSI PENGISIAN-PELEPASAN

2016 ◽  
Vol 6 (1) ◽  
pp. 35
Author(s):  
Daniel Fajar Puspita ◽  
Susanto Sigit Rahardi
Keyword(s):  
Constant Current ◽  
Constant Voltage ◽  
Constant Current Charging

Penelitian  mengenai  stabilisasi  produksi  baterai  ion  litium  berdasarkan  parameter  kapasitas  pengisian, kapasitas pelepasan  dan  efisiensi  pengisian-pelepasan  telah  dilakukan. Tujuan  dari penelitian  ini adalah  untuk mengetahui apakah prosedur pembuatan baterai ion litium ini dapat menghasilkan produk yang homogen. Pada penelitian material selanjutnya hal ini berguna untuk meyakinkan bahwa perubahan kualitas   dari produk baterai yang dihasilkan merupakan pengaruh dari material, bukan karena variabel proses perakitan. Pada penelitian ini dipakai lembaran elektroda siap pakai untuk meniadakan pengaruh variasi bahan baku terhadap kualitas sel baterai yang dihasilkan. Sel baterai dibuat di laboratorium riset baterai B4T. Baterai dibuat sebanyak 3 batch dengan jumlah baterai 8 buah setiap batch. Baterai yang dihasilkan diuji dengan alat battery analyzer merek Berkeley buatan USA dengan arus 0,5 C pada saat constant-current charging dan voltase 4,2 V sewaktu constant-voltage charging selama 10 siklus pada saat uji kinerja  dan arus 0,1 C pada saat pengisian  awal.  Hasil yang didapat adalah  batch C menghasilkan sel-sel baterai yang lebih homogen yang ditandai dengan nilai varians dan simpangan baku yang paling kecil dibandingkan batch lainnya.  Selain itu pada saat uji pengisian-pelepasan  10 siklus, batch C juga memperlihatkan kinerja yang lebih tinggi. Hal ini menunjukkan bahwa proses yang dipakai pada batch C dapat menghasilkan sel baterai ion litium berkinerja baik dan homogen.Kata kunci: stabilisasi produksi, ion litium, kapasitas, efisiensi

scholarly journals A Low Power AC/DC Interface for Wind-Powered Sensor Nodes

Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1823
Author(s):  
Mohammad Haidar ◽  
Hussein Chible ◽  
Corrado Boragno ◽  
Daniele D. Caviglia
Keyword(s):  
Low Power ◽  
Power Supply ◽  
Energy Harvester ◽  
Optimization Techniques ◽  
Sensor Nodes ◽  
Wireless Sensor ◽  
Constant Voltage ◽  
Interface Circuit ◽  
Switching Converter ◽  
Input Signals

Sensor nodes have been assigned a lot of tasks in a connected environment that is growing rapidly. The power supply remains a challenge that is not answered convincingly. Energy harvesting is an emerging solution that is being studied to integrate in low power applications such as internet of things (IoT) and wireless sensor networks (WSN). In this work an interface circuit for a novel fluttering wind energy harvester is presented. The system consists of a switching converter controlled by a low power microcontroller. Optimization techniques on the hardware and software level have been implemented, and a prototype is developed for testing. Experiments have been done with generated input signals resulting in up to 67% efficiency for a constant voltage input. Other experiments were conducted in a wind tunnel that showed a transient output that is compatible with the target applications.

scholarly journals Spectral Broadening in a Continuously Pumped Singly Resonant Second-Harmonic Cavity

2021 ◽  
Vol 11 (15) ◽  
pp. 7122
Author(s):  
Simona Mosca ◽  
Tobias Hansson ◽  
Maria Parisi
Keyword(s):  
Continuous Wave ◽  
Frequency Comb ◽  
Second Harmonic ◽  
Input Power ◽  
Second Order ◽  
Optical Frequency ◽  
Frequency Combs ◽  
Research Areas ◽  
Mixed Regime ◽  
Wide Range

Optical frequency comb synthesizers with a wide spectral range are an essential tool for many research areas such as spectroscopy, precision metrology, optical communication, and sensing. Recent studies have demonstrated the direct generation of frequency combs, via second-order processes, that are centered on two different spectral regions separated by an octave. Here, we present the capability of optical quadratic frequency combs for broad-bandwidth spectral emission in unexplored regimes. We consider comb formation under phase-matched conditions in a continuous-wave pumped singly resonant second-harmonic cavity, with large intracavity power and control of the detuning over several cavity line widths. The spectral analysis reveals quite distinctive sidebands that arise far away from the pump, singularly or in a mixed regime together with narrowband frequency combs. Notably, by increasing the input power, the optical frequency lines evolve into widely spaced frequency clusters, and at maximum power, they appear in a wavelength range spanning up to 100 nm. The obtained results demonstrate the power of second-order nonlinearities for direct comb production within a wide range of pump wavelengths.

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