Surface Wave Couplers for Terahertz Wireless Communication Receiver Front Ends
Yanfeng Zhao,
Jiajun He,
Cong Liu,
Xiaoyuan Hao,
Xizhi Li,
Wei Wu,
Quan Xu,
Xueqian Zhang and
Jiaguang Han
Free-space electromagnetic waves can be coupled into on-chip propagating surface waves (SWs), a process that holds great promise for receiver front-ends in wireless communication systems. However, it has traditionally faced challenges in coupling efficiency and in controlling the on-chip wavefront of SWs. To address these challenges, we design and experimentally demonstrate SW couplers operating in the terahertz regime based on metal-insulator-metal resonators. Our devices achieve not only broadband and highly efficient coupling, with an efficiency exceeding 60% over a 20 GHz bandwidth, but also enable directional steering of the excited SWs to designated on-chip ports. In this way, mode conversion and onchip routing functionalities are seamlessly integrated into a single compact component. Based on this design, we fabricated devices and implemented corresponding terahertz wireless communication links, successfully demonstrating 16-QAM data transmission in both single-link and dual-link configurations.
