Physics:Quantum matter/plasma
Plasma is a state of matter consisting of charged particles such as ions and free electrons. It is often described as an ionized gas and is commonly considered the fourth state of matter after solids, liquids, and gases.[1][2]
Description
Plasma forms when atoms gain sufficient energy for electrons to escape from atomic nuclei, producing a mixture of positively charged ions and negatively charged electrons.[3][4]
Because of the presence of free charges, plasma responds strongly to electromagnetic fields and conducts electricity efficiently.[5][6]
Although plasma is uncommon under ordinary conditions on Earth, it is estimated to constitute more than 99% of the visible matter in the universe.[7][8]
Stars, stellar coronae, nebulae, the solar wind, and much of interstellar space consist primarily of plasma.[9][10]
Plasma also appears naturally on Earth in phenomena such as lightning, aurorae, and sufficiently hot flames.[11]
Properties
Plasma differs from ordinary gases because long-range electromagnetic forces dominate its behavior.[12]
Major properties include:
- composed of ions and free electrons
- electrically conductive
- strongly influenced by electric and magnetic fields
- capable of collective behavior such as plasma waves and instabilities
- often emits visible light
The degree of ionization depends strongly on temperature and density.[13]
In fusion plasmas and stellar interiors, temperatures can reach millions of kelvin.[14]
Plasma and fusion
Plasma plays a central role in magnetic confinement fusion, where powerful magnetic fields are used to confine extremely hot ionized gases.[15]
Fusion experiments such as tokamaks and stellarators attempt to heat plasma to temperatures high enough for nuclear fusion reactions between deuterium and tritium nuclei.[16]
Modern plasma research investigates plasma turbulence, plasma stability, superconducting magnets, and plasma-material interactions for future fusion reactors such as ITER and SPARC.[17]
Applications
Artificial plasmas are widely used in science and technology.[18]
Applications include:
- fluorescent and neon lighting[19]
- plasma displays and plasma televisions[20]
- plasma cutting and welding[21]
- semiconductor etching[22]
- ion thrusters and spacecraft propulsion[23]
- plasma medicine and sterilization[24]
Space plasma
The Earth's ionosphere and magnetosphere contain plasma.[25]
The Sun continuously emits plasma in the form of the solar wind, while astrophysical plasmas are also found in accretion disks, stellar coronae, and relativistic jets around black holes.[26]
History
The electric arc was independently discovered by Vasily Petrov and Humphry Davy in 1803.[9]
In 1879, William Crookes proposed that ionized gases represented a fourth state of matter.[27]
The term plasma was introduced by Irving Langmuir in 1928 while studying ionized gases.[28]
See also
Table of contents (72 articles)
Index
Full contents
References
- ↑ Langmuir, I. (1928). "Oscillations in Ionized Gases". Proceedings of the National Academy of Sciences 14 (8): 627–637. doi:10.1073/pnas.14.8.627. PMID 16587379. Bibcode: 1928PNAS...14..627L.
- ↑ Frank-Kamenetskii, David A. (1972). Plasma-The Fourth State of Matter. Plenum Press. ISBN 9781468418965.
- ↑ Chen, Francis F. (1984). Introduction to Plasma Physics and controlled fusion. Springer International Publishing. pp. 2–3. ISBN 9781475755954.
- ↑ Nicholson, Dwight R. (1983). Introduction to Plasma Theory. John Wiley & Sons. ISBN 978-0-471-09045-8.
- ↑ Freidberg, Jeffrey P. (2008). Plasma Physics and Fusion Energy. Cambridge University Press. p. 121. ISBN 9781139462150.
- ↑ Hazeltine, R.D.; Waelbroeck, F.L. (2004). The Framework of Plasma Physics. Westview Press. ISBN 978-0-7382-0047-7.
- ↑ "Plasma, Plasma, Everywhere!" (in en). https://www.nasa.gov/podcasts/curious-universe/plasma-plasma-everywhere/.
- ↑ "What Is Plasma?". 11 June 2024. https://www.psfc.mit.edu/resources/fusion-101/what-is-plasma/.
- ↑ 9.0 9.1 Piel, A. (2010). Plasma Physics: An Introduction to Laboratory, Space, and Fusion Plasmas. Springer. ISBN 978-3-642-10491-6.
- ↑ Aschwanden, M. J. (2004). Physics of the Solar Corona. An Introduction. Praxis Publishing. ISBN 978-3-540-22321-4.
- ↑ "How Lightning Works". HowStuffWorks. April 2000. http://science.howstuffworks.com/nature/natural-disasters/lightning2.htm.
- ↑ Chen, Francis F. (1984). Introduction to Plasma Physics and controlled fusion. Springer International Publishing. pp. 2–3. ISBN 9781475755954.
- ↑ Morozov, A.I. (2012). Introduction to Plasma Dynamics. CRC Press. ISBN 978-1-4398-8132-3.
- ↑ Bittencourt, J.A. (2004). Fundamentals of Plasma Physics. Springer. ISBN 9780387209753.
- ↑ Peacock, N. J.; Robinson, D. C.; Forrest, M. J.; Wilcock, P. D.; Sannikov, V. V. (1969). "Measurement of the Electron Temperature by Thomson Scattering in Tokamak T3". Nature 224 (5218): 488–490. doi:10.1038/224488a0. Bibcode: 1969Natur.224..488P.
- ↑ Gibney, Elizabeth (2022). "Nuclear-fusion reactor smashes energy record". Nature 602 (7897): 371. doi:10.1038/d41586-022-00391-1.
- ↑ Sweeney, R.; Creely, A. J. (2020). "MHD stability and disruptions in the SPARC tokamak". Journal of Plasma Physics 86 (5): 865860507. doi:10.1017/S0022377820001129.
- ↑ Hippler, R., ed (2008). Low Temperature Plasmas: Fundamentals, Technologies, and Techniques (2nd ed.). Wiley-VCH. ISBN 978-3-527-40673-9.
- ↑ "The Fluorescent Lamp: A plasma you can use". http://www-spof.gsfc.nasa.gov/Education/wfluor.html.
- ↑ Chu, P.K.; Lu, XinPel (2013). Low Temperature Plasma Technology: Methods and Applications. CRC Press. ISBN 978-1-4665-0990-0.
- ↑ Nemchinsky, V. A.; Severance, W. S. (2006). "What we know and what we do not know about plasma arc cutting". Journal of Physics D: Applied Physics 39 (22): R423. doi:10.1088/0022-3727/39/22/R01.
- ↑ National Research Council (1991). Plasma Processing of Materials : Scientific Opportunities and Technological Challenges. National Academies Press. ISBN 978-0-309-04597-1.
- ↑ Peretich, M.A.; O'Brien, W.F.; Schetz, J.A. (2007). Plasma torch power control for scramjet application.
- ↑ Laroussi, M. (1996). "Sterilization of contaminated matter with an atmospheric pressure plasma". IEEE Transactions on Plasma Science 24 (3): 1188–1191. doi:10.1109/27.533129.
- ↑ Kelley, M. C. (2009). The Earth's Ionosphere: Plasma Physics and Electrodynamics. Academic Press. ISBN 9780120884254.
- ↑ "APOD: M87's Energetic Jet". https://apod.nasa.gov/apod/ap041211.html.
- ↑ Von Engel, A. (1955). Ionized Gases. Clarendon Press.
- ↑ Langmuir, I. (1928). "Oscillations in Ionized Gases". Proceedings of the National Academy of Sciences 14 (8): 627–637. doi:10.1073/pnas.14.8.627. PMID 16587379. Bibcode: 1928PNAS...14..627L.
Source attribution: Plasma (physics)









