High-efficiency terahertz surface plasmon metacoupler empowered by bilayer bright–dark mode coupling  

作　　者：ZHIBO YAO XINYAO YUAN YUANHAO LANG FU LI XIAOHAN JIANG XUEQIAN ZHANG QUAN XU YANFENG LI JIAGUANG HAN 

机构地区：[1]Center for Terahertz Waves and College of Precision Instrument and Optoelectronics Engineering,Tianjin University and Key Laboratory of Optoelectronics Information and Technology(Ministry of Education),Tianjin 300072,China [2]Guangxi Key Laboratory of Optoelectronic Information Processing,School of Optoelectronic Engineering,Guilin University of Electronic Technology,Guilin 541004,China

出　　处：《Photonics Research》2024年第11期2495-2507,共13页光子学研究(英文版)

基　　金：National Natural Science Foundation of China(62375203,62075158,62135008,62335011,61935015,62025504);Yunnan Expert Workstation(202205AF150008)。

摘　　要：Conversion from free-space waves to surface plasmons has been well studied as a key aspect of plasmonics.In particular,efficient coupling and propagation of surface plasmons via phase gradient metasurfaces are of great current research interest.Hereby,we demonstrate a terahertz metacoupler based on a bilayer bright–dark mode coupling structure attaining near-perfect conversion efficiency(exceeding 95%)without considering absorption loss of the materials and maintaining a high conversion level even when the area of the excitation region changes.To validate our design,a fabricated metacoupler was assessed by scanning near-field terahertz microscopy.Our findings could pave the way for developing high-performance plasmonic devices encompassing ultra-thin and compact functional devices for a diverse range of applications,especially within the realm of high-speed terahertz communications.

关 键 词：coupling EXCEEDING EXCITATION 

分 类 号：O53[理学—等离子体物理]