Negative-index dispersion and accidental mode degeneracy in an asymmetric spoof-insulator-spoof waveguide  

作　　者：田莉莉 刘建龙 周可雅 高扬 刘树田 

机构地区：[1]Department of Physics, Harbin Institute of Technology [2]College of Electronic Engineering, Heilongjiang University

出　　处：《Chinese Physics B》2017年第7期439-444,共6页中国物理B（英文版）

基　　金：Project supported by the National Basic Research Program of China(Grant No.2013CBA01702);the National Natural Science Foundation of China(Grant Nos.61377016,61575055,10974039,61307072,61308017,and 61405056)

摘　　要：It has been recently demonstrated that negative-index dispersion and mode degeneracy can be achieved by manipulating a spoof-insulator-spoof（SIS） waveguide. In this paper, we propose a new SIS waveguide, which is composed of two spoof surface plasmon polaritons（SSPPs） waveguides drilled with periodic rhomboidal grooves. Both the symmetric and asymmetric cases are investigated. Our simulation results show that the asymmetric SIS waveguides are more significant.By tailoring the tilt of the rhomboidal grooves, the negative-index dispersion can be achieved and the microwave band gap（MBG） can be effectively modulated. At a critical tilt, there appears an accidental mode degeneracy at the edge of the first Brillouin zone. The excitation and propagation of the two coupled modes sustained by the asymmetric SIS waveguides are also demonstrated.It has been recently demonstrated that negative-index dispersion and mode degeneracy can be achieved by manipulating a spoof-insulator-spoof（SIS） waveguide. In this paper, we propose a new SIS waveguide, which is composed of two spoof surface plasmon polaritons（SSPPs） waveguides drilled with periodic rhomboidal grooves. Both the symmetric and asymmetric cases are investigated. Our simulation results show that the asymmetric SIS waveguides are more significant.By tailoring the tilt of the rhomboidal grooves, the negative-index dispersion can be achieved and the microwave band gap（MBG） can be effectively modulated. At a critical tilt, there appears an accidental mode degeneracy at the edge of the first Brillouin zone. The excitation and propagation of the two coupled modes sustained by the asymmetric SIS waveguides are also demonstrated.

关 键 词：spoof surface plasmon polaritons WAVEGUIDE negative index mode degeneracy 

分 类 号：TN252[电子电信—物理电子学]