Effective Surface Plasmon Polaritons Induced by Modal Dispersion in a Waveguide

• Main Authors: Li, Zhuo, Liu, Liangliang, Sun, Hengyi, Sun, Yunhe, Gu, Changqing, Chen, Xinlei, Liu, Yun, Luo, Yu
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2017
• Subjects: Surface plasmon polaritons; Waveguides
• Online Access: https://hdl.handle.net/10356/84048; http://hdl.handle.net/10220/42940
• Institution: Nanyang Technological University

We provide further theoretical insights and experimental verification of the modal-dispersion-induced effective surface-plasmon polaritons (ESPPs) by engineering the transverse-electric (TE) modes in conventional rectangular waveguides. The complete field distributions, dispersion relations, and asymptotic frequency of the ESPPs are derived analytically. Wave-port excitations and smooth bridges are designed for the mode conversion between propagating modes in rectangular waveguides and the ESPPs. Analytical calculations and numerical simulations are performed for TE 10 - and TE 20 -mode-induced ESPPs, showing excellent agreement. Moreover, we design a double-layered substrate-integrated waveguide showing that ESPPs are supported at the interface between the two layers with different dielectric constants. This work opens up an avenue for low-frequency designer surface plasmons and may find potential applications in the design of compact filters, resonators, and sensors of ESPPs in the microwave and terahertz frequencies.