Conference proceeding
Dust in an afterglow plasma can undergo a double reversal in its charge polarity
2023 IEEE International Conference on Plasma Science (ICOPS), pp.1-1
05/21/2023
DOI: 10.1109/ICOPS45740.2023.10480964
Abstract
A dust particle, which is generally negatively charged in a plasma ON condition, becomes positive in an afterglow plasma, after switching the plasma OFF [1]-[3]. We have now found that this positive charging of dust particles can undergo a second reversal, to become negative once again. This occurs if the dust particle is immersed in an electron-rich region of the afterglow plasma. In an experiment, we started with an RF capacitively coupled discharge. Dust particles were levitated above the lower electrode in an RF sheath above the lower electrode, which had a negative dc self-bias. We then suddenly turned OFF the RF power, creating the afterglow condition. Electrons immediately departed the lower electrode region, leaving the dust exposed to a cathodic sheath so that they collected ions only. In this condition, the dust particle's charge reversed, becoming positive within the first 10s of microseconds after turning off the plasma. The second reversal occurred later, after we performed another manipulation, which was the application of a positive dc potential on the lower electrode. When we did this in a certain time range, the remaining electrons in the chamber moved nearer the lower electrode so that they could collect on the dust particles, and charge them negatively once again.
Details
- Title: Subtitle
- Dust in an afterglow plasma can undergo a double reversal in its charge polarity
- Creators
- N. Chaubey - University of IowaJ. Goree - University of Iowa
- Resource Type
- Conference proceeding
- Publication Details
- 2023 IEEE International Conference on Plasma Science (ICOPS), pp.1-1
- Publisher
- IEEE
- DOI
- 10.1109/ICOPS45740.2023.10480964
- eISSN
- 2576-7208
- Grant note
- W911NF-18-1-0240 / Army Research Office (10.13039/100000183) DE-SC0014566 / United States Department of Energy (10.13039/100000015) PHY-1740379 / National Science Foundation (10.13039/100000001)
- Language
- English
- Date published
- 05/21/2023
- Academic Unit
- Physics and Astronomy; Mechanical Engineering
- Record Identifier
- 9984621359402771
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