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Updated: May 10, 2026
08:01
Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
A high spatial resolution Stokes polarimeter for motional Stark effect imaging.
Alex Thorman1, Clive Michael, John Howard
1Plasma Research Laboratory, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200, Australia.
The Review of Scientific Instruments
|July 5, 2013
Summary
We developed an advanced imaging system for KSTAR tokamak plasma diagnostics. This motional Stark effect imaging technique provides high spatial resolution measurements of plasma properties using specialized optics.
Area of Science:
- Plasma Physics
- Optical Engineering
- Fusion Energy Research
Background:
- Accurate plasma diagnostics are crucial for understanding and controlling fusion devices.
- Motional Stark Effect (MSE) imaging is a key diagnostic for measuring magnetic fields and electric fields within plasmas.
- High spatial resolution is needed to resolve fine structures and dynamics in tokamak plasmas.
Purpose of the Study:
- To present an enhanced temporally switched interfero-polarimeter for high spatial resolution MSE imaging.
- To detail the optical system design and its deployment on the KSTAR superconducting tokamak.
- To validate the system's performance using a Mueller matrix model.
Main Methods:
- Utilized dual switching ferroelectric liquid crystal waveplates for polarization analysis.
- Imaged the full Stokes vector of elliptically polarized and Doppler-shifted Stark-Zeeman Balmer-alpha emission.
- Employed high energy neutral beam injection into the magnetized plasma.
Main Results:
- Successfully deployed the enhanced interfero-polarimeter on the KSTAR tokamak.
- Achieved high spatial resolution motional Stark effect imaging.
- Compared experimental performance against a detailed Mueller matrix model accounting for component imperfections.
Conclusions:
- The enhanced interfero-polarimeter is a viable tool for advanced plasma diagnostics.
- The system enables detailed characterization of plasma properties through MSE imaging.
- Accurate modeling is essential for interpreting polarization measurements from complex optical systems.
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