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Updated: Sep 11, 2025
09:33
Demonstration of Equal-Intensity Beam Generation by Dielectric Metasurfaces
Published on: June 7, 2019
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Terahertz metasurface with polarization conversion and Gaussian beam shaping
Applied Optics
|August 12, 2025
Summary
This study introduces a compact terahertz metasurface capable of converting Gaussian beams to flat-top beams and changing polarization. This innovative device offers high efficiency and a wide operating bandwidth for terahertz applications.
Area of Science:
- Metasurface technology
- Terahertz optics
- Beam shaping
Background:
- Conventional beam conversion methods often utilize bulky lens systems.
- There is a need for compact and efficient beam shaping devices in the terahertz frequency band.
Purpose of the Study:
- To propose and demonstrate a novel terahertz metasurface for Gaussian to flat-top beam conversion.
- To achieve simultaneous cross-polarization conversion of terahertz waves.
Main Methods:
- Design and simulation of a terahertz metasurface with adjustable metal split rings.
- Utilizing an improved Gerchberg-Saxton (GS) algorithm for phase distribution calculation.
- Achieving full 2π phase coverage through structural adjustments.
Main Results:
- Demonstrated conversion of Gaussian beam to flat-top beam with high shaping efficiency.
- Achieved cross-polarization conversion efficiency exceeding 70% over a relative bandwidth of 93.3% (0.4-1.1 THz).
- Obtained a high-quality flat-top beam with low RMS error (0.143) and non-uniformity (0.126).
Conclusions:
- The proposed metasurface offers a compact, wide-bandwidth, and efficient solution for terahertz beam shaping.
- This technology presents an innovative approach for terahertz wave manipulation.
- The device exhibits low transmission loss and high shaping efficiency, suitable for practical applications.
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