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Linear to radial polarization conversion in the THz domain using a passive system
1Institut FEMTO-ST, Université de Franche-Comté, UMR 6174 CNRS, Département d'Optique P.M. Duffieux, Besançon cedex, France. thierry.grosjean@univ-fcomte.fr
Optics Express
|July 8, 2009
Summary
This study presents a passive system that converts linearly polarized terahertz (THz) beams into radially polarized ones using a circular waveguide and tapers. The validated 0.1 THz prototype is adaptable for higher frequencies.
Area of Science:
- Terahertz (THz) technology
- Waveguide optics
- Polarization control
Background:
- Efficient manipulation of terahertz (THz) beams is crucial for advanced applications.
- Converting linear polarization to radial polarization is a key challenge in THz optics.
Purpose of the Study:
- To develop and validate a passive system for converting linearly polarized THz beams to radially polarized beams.
- To adapt existing optical fiber concepts for THz waveguide applications.
Main Methods:
- Utilized a circular waveguide with two tapers to achieve mode selection.
- Extended optical fiber mode selection principles to THz frequencies.
- Fabricated and tested a prototype system at 0.1 THz.
Main Results:
- Successfully converted a linearly polarized THz beam into a radially polarized output.
- Demonstrated the system's functionality at 0.1 THz.
- Confirmed the scalability of the design for higher THz frequencies via size reduction.
Conclusions:
- The proposed passive system effectively achieves THz beam polarization conversion.
- The waveguide-based approach offers a viable alternative to optical fiber methods for THz applications.
- The design's simplicity allows for easy adaptation to various THz frequencies.
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