In this paper, a non-Hermitian graphene plasmonic waveguide system is proposed in the mid-infrared region. The proposed structure consists of two resonators and a graphene waveguide, which are attached to the SiO₂ substrate. Based on the far-field coupling between the two stub plasmonic resonators, the single-band unidirectional reflectionless phenomenon of fundamental edge plasmonic mode in the non-Hermitian waveguide system has been theoretically studied. It can be found that when plasmonic mode is incident from one side, the reflection is 0, but from the other side, the reflection is 26.212%, so an exceptional point (EP) appears. Furthermore, the EP blueshifts with increasing Fermi level, and is unchanged under different relaxation times. All the simulation results are conducted by finite element method. Therefore, our findings pave a new way for the development of terahertz sensors, diodes, and so on.

本文提出了一种在中红外区域的非赫米特石墨烯等离子体波导系统。所提出的结构包括两个谐振器和一个石墨烯波导，它们连接到SiO _2上基质。基于两个短线等离子体谐振器之间的远场耦合，从理论上研究了非埃尔米特波导系统中基本边缘等离子体模式的单波段单向无反射现象。可以发现，当等离子体激元模式从一侧入射时，反射率为0，而从另一侧入射，则反射率为26.212％，因此会出现一个例外点（EP）。此外，EP随费米能级的增加而蓝移，并且在不同的弛豫时间下保持不变。所有的仿真结果都是通过有限元方法进行的。因此，我们的发现为开发太赫兹传感器，二极管等铺平了道路。