Unidirectional surface plasmon-polariton excitation by a compact slot partially filled with dielectric

• Main Authors: Li, Dongdong, Zhang, Dao Hua, Yan, Changchun, Li, Tao, Wang, Yueke, Xu, Zhengji, Wang, Jun, Qin, Fei
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Electrical and electronic engineering
• Online Access: https://hdl.handle.net/10356/96432; http://hdl.handle.net/10220/9921
• Institution: Nanyang Technological University

We propose a new scheme on unidirectional surface plasmonpolariton (SPP) excitation with the following advantages: ultracompact size, working at arbitrary incidence angle and over a wide spectrum. The proposed structure utilizes a partially filled metallic slot with dielectric to realize unidirectional SPP excitation via direct field manipulation. We theoretically and numerically show that unidirectional SPP excitation with a ratio of 93% can be achieved by a structure with a 50 nm slot. The proposed structure keeps its functional capability over incident angles from −80° to 80°, and has a broadband working spectrum of more than 70 nm.