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Updated: Jun 18, 2026
08:01
Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
A magneto-optic probe for magnetic fluctuation measurements
W S Przybysz1, J Ellis, S Chakraborty Thakur
1Department of Physics, West Virginia University, Morgantown, West Virginia 26506, USA.
The Review of Scientific Instruments
|November 10, 2009
Summary
A novel optical probe enables precise measurement of plasma magnetic field fluctuations. This compact, robust device offers superior performance over traditional coil probes, unaffected by frequency or electrostatic interference.
Area of Science:
- Plasma physics
- Optical diagnostics
- Magnetometry
Background:
- Accurate measurement of magnetic field fluctuations is crucial for understanding plasma behavior.
- Conventional coil probes face limitations such as frequency dependence and susceptibility to electrostatic noise.
Purpose of the Study:
- To demonstrate a proof-of-principle for a completely optical, compact, and robust probe for measuring magnetic field fluctuations in plasma.
- To overcome the limitations of conventional magnetic field measurement techniques.
Main Methods:
- Utilized a high Verdet constant crystal, two polarizers, optical fibers, and a photodetector.
- Developed an optical measurement technique for spatially resolved magnetic field fluctuation detection.
Main Results:
- Successfully constructed a compact, robust, and completely optical probe.
- Achieved sensitive measurements of magnetic field fluctuations (<1 G) over a wide frequency range (1 Hz-8 MHz).
- Demonstrated signal independence from fluctuation frequency and immunity to electrostatic pickup.
Conclusions:
- The developed optical probe is a viable alternative to conventional coil probes for plasma diagnostics.
- This technology offers enhanced robustness, compactness, and immunity to interference for magnetic field measurements.
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