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Updated: Apr 27, 2026
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The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
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Generation of broadband terahertz vortex beams
Optics Letters
|July 1, 2014
Summary
We developed a new method to create broadband terahertz (THz) vortex beams, controlling their topological charge. This breakthrough enables advanced THz wave applications in sensing and communication.
Area of Science:
- Optics and Photonics
- Terahertz Science and Technology
Background:
- Terahertz (THz) beams possess unique properties.
- Vortex beams, with orbital angular momentum, offer advanced functionalities.
Purpose of the Study:
- To propose and demonstrate a method for generating broadband THz vortex beams.
- To characterize the topological charge and its control.
Main Methods:
- Conversion of radially polarized THz beams into vortex beams using achromatic polarization optical elements.
- Spatial phase distribution measurement at the focal plane to characterize topological charge.
Main Results:
- Generation of broadband THz vortex beams.
- Achieved uniform topological charge (e.g., +1) over a wide frequency range.
- Demonstrated easy control over the sign of the topological charge.
Conclusions:
- The developed method successfully generates broadband THz vortex beams with controllable topological charge.
- This technique paves the way for novel THz wave applications in sensing, manipulation, and telecommunication.
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