Laser-induced breakdown spectroscopy (LIBS) has become a very popular analytical method in the last decade in view of some of its unique features such as applicability to any type of sample, practically no sample preparation, remote sensing capability, and speed of analysis The technique has a remarkably wide applicability in many fields, and the number of applications is still growing From an analytical point of view, the quantitative aspects of LIBS may be considered its Achilles' heel, first due to the complex nature of the laser–sample interaction processes, which depend upon both the laser characteristics and the sample material properties, and second due to the plasma–particle interaction processes, which are space and time dependent Together, these may cause undesirable matrix effects Ways of alleviating these problems rely upon the description of the plasma excitation-ionization processes through the use of classical equilibrium relations and therefore on the assumption that the laser-induced 

Laser-Induced Breakdown Spectroscopy (LIBS), Part I: Review of Basic Diagnostics and Plasma–Particle Interactions: Still-Challenging Issues Within the Analytical Plasma Community

The density of metastable helium atoms in a dielectric barrier discharge operating in helium with some impurities present has been measured using laser-collisional-induced fluorescence and absorption techniques. Time-resolved measurements indicate that helium metastables contribute to the production of impurity ions, in this case N2+, in the postdischarge current phase of a glow discharge. In our particular discharge environment, the helium metastable density is (1.5±1.4)×1010cm−3, a result consistent with failure to observe absorption by metastables in a multipass absorption measurement.

Measurements of helium metastable density in an atmospheric pressure glow discharge

We discuss the application of the laser-collisional induced fluorescence (LCIF) technique to produce two-dimensional maps of both electron densities and electron temperatures in a helium plasma. A collisional–radiative model (CRM) is used to describe the evolution of electronic states after laser excitation. We discuss generalizations to the time dependent results which are useful for simplifying data acquisition and analysis. LCIF measurements are performed in plasma containing densities ranging from ~109 electrons cm−3 and approaching 1011 electrons cm−3 and comparison is made between the predictions made by the CRM and the measurements. Finally, spatial and temporal evolution of an ion sheath formed during a pulse bias is measured to demonstrate this technique.

https://iopscience.iop.org/article/10.1088/0963-0252/19/5/055015/pdf

Two-dimensional mapping of electron densities and temperatures using laser-collisional induced fluorescence

Laser‐collision induced fluorescence (LCIF) is the emission of light from states that have been populated by laser excitation and a subsequent collision. By simultaneously measuring the LCIF from two different states, it is possible to determine both the electron density and temperature of the low energy bulk electrons within a plasma. This method is described in detail and has been applied in the determination of the total, temporally averaged, and spatially resolved electron density in a rf (13.56 MHz) helium discharge in the Gaseous Electronics Conference reference cell. The rf discharge was operated at pressures P=33.3–133.3 Pa (0.25–1.0 Torr) and peak‐to‐peak voltages of Vpp=75–300 V were applied. We found the total electron density varied from 1.8×108 cm−3 at P=33.3 Pa and Vpp=75 V to 4.0×1010 cm−3 at P=133.3 Pa and Vpp=300 V. A comparison of results from different experiments has been made.

Electron density measurement in a rf helium plasma by laser‐collision induced fluorescence method

A review of work centered on the utilization of multi-dimensional optical diagnostics to study phenomena arising in radiofrequency plasma discharges is given. The diagnostics range from passive techniques such as optical emission to more active techniques utilizing nanosecond lasers capable of both high temporal and spatial resolution. In this review, emphasis is placed on observations that would have been more difficult, if not impossible, to make without the use of such diagnostic techniques. Examples include the sheath structure around an electrode consisting of two different metals, double layers that arise in magnetized hydrogen discharges, or a large region of depleted argon 1s4 levels around a biased probe in an rf discharge.

Multi-dimensional optical and laser-based diagnostics of low-temperature ionized plasma discharges

A new method based on the laser-induced fluorescence method has been developed to measure the spatial electron density distribution in plasmas. The local electron density can be determined by observing the intensity ratio of the laser- to the collision-induced fluorescence. A spatial electron density distribution of a helium plasma (Te approximately 6 eV, ne:1011-12 cm-3) has been determined by observing the He(31P to 21S) laser-induced fluorescence and the He(31D to 21P) collision-induced fluorescence resulting from the He(31P to 31D) process due to collisions with electrons. The comparison of the result with that of a conventional method proves this new method is of practical use in the space-resolved measurements of plasma electron density.

Plasma electron density measurements by the laser- and collision-induced fluorescence method

Plasma electron density measurements by laser- and collision-induced fluorescence method

Neutral beam probe spectroscopy for edge plasma diagnostics

A method combining the techniques of laser blowoff and laser‐induced fluorescence has been developed in order to measure the local electron density below 1013 cm−3. Characteristics of a Li0 beam produced by laser blowoff of a thin Li film are investigated using beam–plasma interactions and laser‐induced fluorescence. Such a beam has a near‐Maxwellian velocity distribution with a temperature around 4.5 eV and a density of the order of 1010 cm−3 at a distance of about 1 m from the film target. The feasibility of measuring electron density with this Li0 beam and a dye laser is demonstrated with an ECR plasma.

Measurement of electron density with combined technique of laser blowoff and laser-induced fluorescence

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.

K. Tsuchida

Author Tools

Chat about Author

Papers

Plasma electron density measurements by the laser- and collision-induced fluorescence method

Plasma electron density measurements by laser- and collision-induced fluorescence method

Neutral beam probe spectroscopy for edge plasma diagnostics

Measurement of electron density with combined technique of laser blowoff and laser-induced fluorescence