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Updated: May 16, 2025
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Demonstration of Equal-Intensity Beam Generation by Dielectric Metasurfaces
Published on: June 7, 2019
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Polarization variable terahertz metasurface along the propagation path.
Jitao Li1, Jingyu Liu2, Zhen Yue1
1Key Laboratory of Opto-Electronics Information Technology (Tianjin University), Ministry of Education, School of Precision Instruments and Opto-Electronics Engineering, Tianjin University, Tianjin 300072, China.
Fundamental Research
|April 1, 2025
Summary
Researchers developed a novel terahertz metasurface for longitudinal polarization control, enabling dynamic polarization rotation along the propagation path for advanced sensing and communication applications.
Area of Science:
- Optics and Photonics
- Metasurface Technology
- Terahertz Science
Background:
- Conventional metasurfaces offer limited lateral control of terahertz wave polarization.
- Existing technologies maintain a constant polarization state along the wave's propagation path.
Purpose of the Study:
- To propose and design a terahertz metasurface capable of longitudinal polarization control.
- To achieve dynamic modification of polarization states along the propagation axis.
Main Methods:
- Designed a metasurface to independently control phase delays of left-handed (LCP) and right-handed circularly polarized (RCP) terahertz waves.
- Engineered distinct propagation paths for LCP and RCP beams to form a Bessel beam.
- Achieved a precise, propagation-dependent phase difference (Δφ) between LCP and RCP components.
Main Results:
- Demonstrated longitudinal control, modifying polarization states along the z-axis.
- Generated a linearly polarized terahertz wave with a rotation angle varying from 0 to π along the propagation path.
- Proposed a dielectric refractive index sensing concept based on detecting polarization rotation.
Conclusions:
- The developed metasurface enables unprecedented longitudinal polarization control in the terahertz regime.
- The technology shows potential for applications in dielectric refractive index sensing, variable media excitation, terahertz communication, and radar ranging.
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