相关论文: Coupling of RF Antennas to Large Volume Helicon Pl…
Inductively coupled plasma (ICP) attracts great attention from aspects of fundamental research and practical applications, and efficient power coupling is highly desirable for both of them. The present study explores a novel strategy for…
Plasma wakefield accelerators (PWA), such as AWAKE, require homogenous high-density plasmas. The Madison AWAKE Prototype (MAP) has been built to create a uniform argon plasma in the $10^{20}\,\mathrm{m^{-3}}$ density range using helicon…
Waves propagating along a converging-diverging rf magnetoplasma having the characteristics of a bounded m=0 helicon mode are reported and characterised. The discharge features a 30 cm separation between the region of radiofrequency energy…
Radio-frequency discharges are performed in low magnetic fields (0-10 mT) using three types of helicon-wave exciting antennas with the azimuthal mode number of $|m|$ = 1. The most pronounced peak of plasma density is generated in the case…
The ionization efficiency of helicon plasma discharge is explored by changing the low axial magnetic field gradients near the helicon antenna. The highest plasma density is found for a most possible diverging field near the antenna by…
A highly-efficient multi-resonant RF energy-harvesting rectenna based on a metamaterial perfect absorber featuring closely-spaced polarization-independent absorption modes is presented. Its effective area is larger than its physical area,…
Helicon plasmas are being considered as plasma sources for wakefield accelerators, subject to strict density requirements. We present various mechanisms to increase axial density homogeneity in a helicon plasma for implementation in such an…
This paper reports an innovative concept of ``plasma fibre" using bright-core helicon plasma, inspired by its spatial and spectral similarities to the well-known optical fibre. Theoretical analyses are presented for both ideal case of…
The current study, as part of a PhD project on the design of a helicon thruster, aims to provide a rational methodology for the design of the helicon thruster's main component, i.e., the helicon antenna. A helicon thruster is an innovative…
The coupling physics between multiple antennas separated axially along a plasma cylinder is investigated. Experiments are carried out on a recently built device: Physics ANd Thruster oriented HElicon Research (PANTHER), with an upgrade of…
Hairpin probes measure electron density in plasmas where other techniques are unsuitable. Previous hairpins were constructed as a quarter-wave resonant structure typically made from a folded piece of wire. The present work conducts the…
Radio-frequency (RF) driven helicon plasma sources can produce relatively high-density plasmas (n > 10^19 m-3) at relatively moderate powers (< 2 kW) in argon. However, to produce similar high-density plasmas for fusion relevant gases such…
When an electromagnetic wave is obliquely incident on an inhomogeneous high density plasma, it will be absorbed resonantly as long as it is polarized in the plane of incidence and has an electric field component along the plasma electron…
We propose a new strategy to search for dark matter axions using tunable cryogenic plasmas. Unlike current experiments, which repair the mismatch between axion and photon masses by breaking translational invariance (cavity and dielectric…
A broadband sound absorption attained by a deep-subwavelength structure is of great interest to the noise control community especially for extremely low frequencies (20-100 Hz) in room acoustics. Coupling multiple different resonant unit…
Existence of the density limit in the helicon plasma sources is critically revisited. The low- and high-frequency regimes of a helicon plasma source operation are distinguished. In the low-frequency regime with $\omega <…
Both the radiation efficiency and bandwidth of electrically small antennas are dramatically reduced as the size decreases. Fundamental limitations on the bandwidth of small antennas have been thoroughly treated in the past. However, upper…
A birdcage resonant helicon antenna is designed, mounted and tested in the toroidal device TORPEX. The birdcage resonant antenna is an alternative to the usual Boswell or half-helical antenna designs commonly used for $\sim$ 10 cm diameter…
Low-pressure multi-frequency capacitively coupled plasmas are used for numerous etch and deposition applications in the semiconductor industry. Pulsing of the radio-frequency (RF) sources enables control of neutral and charged species in…
This paper describes three-dimensional numerical simulations and Radio Frequency (RF) measurements of wave propagation in microwave-heated magnetized plasmas of ion sources. Full-wave solution of Maxwell's equations has been addressed…