The development of a large magnetized plasma source for wave propagation experiments is described. The method employs a dc discharge in a weak magnetic field region and subsequent particle diffusion into a strong, uniform B‐field region. The resultant steady‐state plasma is uniform (8 cm⊥B0, 120 cm∥B0), quiescent (δn/n≲1%), has high density (ne≳1011 cm−3), a B0=1 kG, argon (3×10−4 Torr), and low collision rates (νen≃105 sec−1). The source can be easily scaled to larger dimensions. Plasma diagnostics with probes, microwaves, and spectroscopy for steady state and afterglow are described. Examples of wave propagation for ion acoustic waves, electron Bernstein waves, and lower hybrid waves indicate the versatility of the device.

Large, quiescent, magnetized plasma for wave studies

The paper deals with the experimental study of the absorption of microwave energy in plasma in a strong magnetic field, omega ce/ omega >>1, where omega ce and omega are the electron cyclotron and wave frequency respectively. The microwave energy is delivered to the plasma by a cylindrical helical structure. The experiments have verified the possibility of efficient absorption of the microwave energy for ratios up to omega ce/ omega =14. It was found that the absorption is practically independent of the magnetic field, and for magnetic fields lying in the interval omega ce/ omega in (1, 14) is nearly constant.

Absorption of electromagnetic waves in a radially inhomogeneous plasma at high magnetic fields

This paper presents results of high-density plasma production experiments carried out using an optimally designed and excited slotted helical antenna. The slotted helical antenna was excited by linearly polarized, right-hand polarized (RHP) and left-hand polarized (LHP) CW microwaves (f = 2.45 GHz) with power up to 2.5 kW. Two different discharges - the resonant and the non-resonant discharges - were studied. In the resonant discharges the magnetic field at the edge of the helical antenna was equal to the ECR field, so that a resonant coupling of the electrons and the microwaves could occur. In non-resonant discharges the value of the magnetic field was greater than the resonant field throughout the mirror. It was seen that the linearly polarized and RHP waves can produce about 100% ionization (at pressures Torr; power kW) for both resonant and non-resonant discharges. In most cases an enhancement over the neutral particle density could be observed due to improved confinement. The resonant discharge using LHP waves also yielded similar results as obtained using the RHP and the linearly polarized waves. This result is somewhat unexpected since the LHP waves are not expected to undergo resonance at electron cyclotron resonance. The non-resonant discharge using LHP waves was found to be very weak (underdense). Finally, an attempt has been made to understand the unexpected nature of the resonant discharges using LHP waves, in terms of the modes of plasma loaded helices and waveguides.

https://iopscience.iop.org/article/10.1088/0963-0252/6/2/013/pdf

High-density plasma production using a slotted helical antenna at high microwave power

Investigations on the optimization of feed structures for exciting the slotted line antenna for high-density plasma production are presented. Each feed structure used (except the direct feed) excites a preferred component of the wave electric/magnetic field. It is seen that the efficacy of plasma production using the different feeds depends directly on the relative importance of the field components (which the feeds excite) for the flow wave mode of the antenna. The optimal feed is shown to be a dipole antenna, oriented so as to excite the radial component of the electric field within the slotted line structure. The plasma characterization results as a function of the input microwave power and the magnetic field in the antenna region are also presented and discussed. The ability of the antenna to maintain high-density plasmas well away from electron-cyclotron resonance is demonstrated. >

Feed optimization for the slotted line antenna for high-density plasma production

Absorption of microwave energy in a plasma column at high magnetic fields

The main features of a helical microwave plasma source with a magnetic field in the range 1<or=Fce/F<or=30 and with a plasma density 1011<or=Ne<or=1013 cm-3, for hydrogen and argon plasmas.

Operating properties of a helical microwave plasma source in high density high magnetic field regime

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

R. Cano

Author Tools

Chat about Author

Papers

Operating properties of a helical microwave plasma source in high density high magnetic field regime