Terahertz orbital angular momentum: Generation, detection and communication

• Published in: China communications Vol. 18; no. 5; pp. 131 - 152
• Main Authors: Yang, Hang, Zheng, Shilie, He, Wei, Yu, Xianbin, Zhang, Xianmin
• Format: Journal Article
• Language: English
• Published: China Institute of Communications 01-05-2021; College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China; Zhejiang Lab, Hangzhou 311121, China%College of Information Science and Electronic Engineering, Zhejiang University, Hangzhou 310027, China
• Subjects: Laser beams; Metasurfaces; Optical pulses; Optical refraction; Optical vortices; orbital angular momentum; Quantum cascade lasers; terahertz detection; terahertz generation; terahertz vortex beam; Wireless communication; terahertz generation; orbital angular momentum; terahertz detection; terahertz vortex beam
• ISSN: 1673-5447
• DOI: 10.23919/JCC.2021.05.009

To accommodate the ever-increasing wireless capacity, the terahertz (THz) orbital angular momentum (OAM) beam that combines THz radiation and OAM technologies has attracted much attention recently, with contributing efforts to explore new dimensions in the THz region. In this paper, we provide an overview of the generation and detection techniques of THz-OAM beams, as well as their applications in communications. The principle and research status of typical generation and detection methods are surveyed, and the advantages and disadvantages of each method are summarized from a viewpoint of wireless communication. It is shown that developing novel THz components in generating, detecting and (de)multiplexing THz-OAM beams has become the key engine to drive this direction forward. Anyway, beneficial from the combination of infinite orthogonal modes and large bandwidth, THz-OAM beams will have great potential in delivering very large capacity in next generation wireless communications.