Related Experiment Video
Updated: May 28, 2026
09:33
Demonstration of Equal-Intensity Beam Generation by Dielectric Metasurfaces
Published on: June 7, 2019
Angle-Dependent Terahertz Circular Dichroism and Full-Space Polarization Manipulation via Extrinsic Chiral
Mengxiang Wan1,2, Jiahao Shen1,2, Hang Xu3
1Sichuan Province Key Laboratory of Optoelectronic Sensor Devices and Systems, College of Optoelectronic Engineering (Chengdu IC Valley Industrial College), Chengdu University of Information Technology, Chengdu 610225, China.
Nanomaterials (Basel, Switzerland)
|May 26, 2026
Summary
This study introduces an extrinsic chiral metasurface for terahertz waves. It achieves full-space polarization beam splitting and strong circular dichroism by controlling incident angles.
Area of Science:
- Photonics and Metamaterials
- Terahertz Science and Technology
Background:
- Extrinsic chiral metasurfaces enable chiroptical response control via incident angle.
- Simultaneously achieving strong circular dichroism and full-space polarization beam splitting is a significant challenge.
Purpose of the Study:
- To propose and demonstrate an all-dielectric extrinsic chiral metasurface for terahertz waves.
- To achieve angle-dependent, full-space polarization manipulation, including circular dichroism and beam splitting.
Main Methods:
- Utilizing obliquely incident terahertz waves on an all-dielectric extrinsic chiral metasurface.
- Breaking in-plane symmetry to activate out-of-plane multipoles and induce spin-selective scattering.
- Analyzing the metasurface's performance at a 30° incident angle near 0.48 THz.
Main Results:
- Achieved efficient full-space separation of left- and right-handed circularly polarized waves.
- Demonstrated a peak circular dichroism exceeding 0.7 at 0.48 THz.
- Showcased continuous tuning of reflected wave polarization (linear, elliptical, circular) via incident angle and frequency variation.
Conclusions:
- The proposed metasurface effectively controls chiroptical responses and achieves full-space polarization beam splitting.
- The angle-dependent polarization manipulation capability is suitable for advanced terahertz applications.
- Highlights potential for terahertz imaging, LiDAR, and integrated photonic systems.
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