Terahertz (THz) wireless links have attracted significant attention due to their pivotal role in next-generation communication systems. Multiplexing is one of the key techniques used to expand channel capacity for high-speed data transmission in point-to-point wireless communication. Using a pair of multifunction metasurfaces, we construct mode division multiplexing (MDM) in THz wireless link with cylindrical vector beams (CVBs) as orthogonal channels. The proposed metasurfaces integrate the functions of CVB generation and vector mode multiplexing, greatly simplifying MDM links. The simulated and measured results show that the multiplexer/demultiplexers are broadband in the frequency range of concern (from 0.36 to 0.44 THz) and compatible with frequency-division-multiplexing and polarization-division-multiplexing. Importantly, we experimentally accomplished a two-channel MDM in a direct modulation THz communication system at 0.36 THz in which the maximum modulation speed is 5 GHz (isolation>20dB). This study will lay the groundwork for CVB-based multidimensional multiplexing in the THz spectrum, potentially enhancing high-capacity THz communication.
This content will become publicly available on February 19, 2025
Metasurfaces have been continuously garnering attention in both scientific and industrial fields owing to their unprecedented wavefront manipulation capabilities using arranged subwavelength artificial structures. Terahertz vortex beams have become a focus of research in recent years due to their prominent role in many cutting-edge applications. However, traditional terahertz vortex beam plates are often faced with challenges including large size, low efficiency, and limited working bandwidth. Here, we propose and experimentally demonstrate highly efficient and broadband vortex beam plates based on metasurface in the terahertz region. The experimental results well verify that the designed metasurfaces can efficiently generate terahertz vortex beams with different orbital angular momentum topological charges in the range of 0.5–1 THz. Notably, the maximum efficiency can reach about 65% at 0.5 THz. The proposed devices may play a vital role in developing vortex beams-related terahertz applications.
more » « less- Award ID(s):
- 2114103
- PAR ID:
- 10538228
- Publisher / Repository:
- AIP Publishing
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 124
- Issue:
- 8
- ISSN:
- 0003-6951
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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