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Total Internal Reflection Absorption Spectroscopy TIRAS for the Detection of Solvated Electrons at a Plasma-liquid Interface
Published on: January 24, 2018
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Infrared spectroscopy of surface charges in plasma-facing dielectrics
K Rasek1, F X Bronold1, H Fehske1
1Institut für Physik, Universität Greifswald, 17489 Greifswald, Germany.
Physical Review. E
|August 20, 2021
Summary
This study introduces a new infrared spectroscopy method to measure surface charge at plasma-dielectric interfaces. The technique efficiently quantifies charge by analyzing signal attenuation, offering a powerful diagnostic tool.
Area of Science:
- Plasma physics
- Surface science
- Optical spectroscopy
Background:
- Accurate measurement of surface charge at plasma-dielectric interfaces is crucial for understanding plasma-material interactions.
- Existing methods may lack efficiency or direct surface sensitivity.
Purpose of the Study:
- To develop and validate a novel, efficient method for quantifying surface charge density at plasma-dielectric interfaces.
- To utilize infrared spectroscopy combined with internal reflection for enhanced sensitivity.
Main Methods:
- Employing infrared spectroscopy with the dielectric material acting as a multi-internal reflection element.
- Calculating the optical response perturbatively from the Boltzmann equation for the electron-hole plasma.
- Analyzing the attenuation of the transmitted infrared signal.
Main Results:
- Demonstrated that the surface charge magnitude can be directly inferred from signal attenuation.
- Showed that a classical Drude term describes the optical response in the relevant parameter range.
- Confirmed that only the integrated surface charge influences the measured signal, simplifying analysis.
Conclusions:
- The proposed infrared spectroscopy method provides an efficient and direct means to measure surface charge at plasma-dielectric interfaces.
- This technique offers a simplified analysis of experimental data, relying solely on integrated surface charge.
- The findings pave the way for improved diagnostics in plasma processing and material science.
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