Circulation of spoof surface plasmon polaritons: Implementation and verification

• Published in: AIP advances Vol. 8; no. 5; pp. 055002 - 055002-6
• Main Authors: Pan, Junwei, Wang, Jiafu, Qiu, Tianshuo, Pang, Yongqiang, Li, Yongfeng, Zhang, Jieqiu, Qu, Shaobo
• Format: Journal Article
• Language: English
• Published: AIP Publishing LLC 01-05-2018
• ISSN: 2158-3226; 2158-3226
• DOI: 10.1063/1.5020670

In this letter, we are dedicated to implementation and experimental verification of broadband circulator for spoof surface plasmon polaritons (SSPPs). For the ease of fabrication, a circulator operating in X band was firstly designed. The comb-like transmission lines (CL-TLs), a typical SSPP structure, are adopted as the three branches of the Y-junction. To enable broadband coupling of SSPP, a transition section is added on each end of the CL-TLs. Through such a design, the circulator can operate under the sub-wavelength SSPP mode in a broad band. The simulation results show that the insertion loss is less than 0.5dB while the isolation and return loss are higher than 20dB in 9.4-12.0GHz. A prototype was fabricated and measured. The experimental results are consistent with the simulation results and verify the broadband circulation performance in X band.