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Hydrogen plasma induced photoelectron emission from metal surfaces
Low temperature hydrogen plasmas are strong sources of vacuum ultraviolet radiation. The properties of laboratory plasmas can be inﬂuenced by surface processes induced by photons with their energies exceeding the surface work function of the wall material. In this work, the plasma induced photoelectron emission has been studied with different ion sources. The emission depends on the mechanical design of the plasma device, plasma heating method and the discharge power (density). Parametric studies include the quantifying of the emission from different metal surfaces, commonly used as plasma facing materials in ion sources, as well as alkali metal covered surfaces. Experimental studies suggest that low temperature hydrogen plasma induced photoelectron emission from metal surfaces can reach an order of magnitude of 1 A per kW of plasma heating power. Furthermore, the emission can increase 2–3.5 times when the metal surface is coated with a thin layer of alkali metal reducing the work function. The free electrons produced by the photoelectron emission can inﬂuence various plasma processes and especially the plasma sheath structure, which has been studied using a one-dimensional analytical model. ...
PublisherUniversity of Jyväskylä
ISSN Search the Publication Forum0075-465X
- Artikkeli I: Laulainen, J., Kalvas, T., Koivisto, H., Komppula, J. and Tarvainen, O. (2015). Photoelectron emission from metal surfaces induced by VUV-emission of filament driven hydrogen arc discharge plasma. AIP Conference Proceedings, 1655, 020007. DOI: 10.1063/1.4916416
- Artikkeli II: Laulainen, J., Kalvas, T., Koivisto, H., Komppula, J., Kronholm, R., & Tarvainen, O. (2016). Photoelectron emission from metal surfaces induced by radiation emitted by a 14 GHz electron cyclotron resonance ion source. Review of Scientific Instruments, 87(2), Article 02A506. DOI: 10.1063/1.4935012
- Artikkeli III: Laulainen, J., Kalvas, T., Koivisto, H., Kronholm, R., Tarvainen, O., Aleiferis, S., & Svarnas, P. (2017). Photoelectron emission experiments with ECR-driven multi-dipolar negative ion plasma source. In D. Faircloth (Ed.), NIBS 2016 : Fifth International Symposium on Negative Ions, Beams and Sources (Article 020012). AIP Publishing. AIP Conference Proceedings, 1869. DOI: 10.1063/1.4995718
- Artikkeli IV: Laulainen, J., Aleiferis, S., Kalvas, T., Koivisto, H., Kronholm, R., & Tarvainen, O. (2017). Hydrogen plasma induced photoelectron emission from low work function cesium covered metal surfaces. Physics of Plasmas, 24(10), Article 103502. DOI: 10.1063/1.4998005
- Artikkeli V: Laulainen, J., Kalvas, T., Koivisto, H., Kronholm, R., & Tarvainen, O. (2018). Photoelectron emission induced by low temperature hydrogen plasmas. In J. Lettry, E. Mahner, B. Marsh, R. Pardo, & R. Scrivens (Eds.), Proceedings of the 17th International Conference on Ion Sources (Article 020001). AIP Publishing. AIP Conference Proceedings, 2011. DOI: 10.1063/1.5053243
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- Väitöskirjat 
Showing items with similar title or keywords.
VUV-diagnostics of low temperature hydrogen plasmas Komppula, Jani (University of Jyväskylä, 2015)
Photoelectron emission induced by low temperature hydrogen plasmas Laulainen, Janne; Kalvas, Taneli; Koivisto, Hannu; Kronholm, Risto; Tarvainen, Olli (AIP Publishing, 2018)Experimental results of low temperature hydrogen plasma induced photoelectron emission measurements comparing two different plasma heating methods are summarized. By exposing the samples to the vacuum ultraviolet radiation ...
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