Magnetically tunable terahertz dual-band band-stop filters are proposed based on the surface magnetoplasmons of graphene. The magnetoplasmons of a graphene rectangular sheet array can be attributed to the combination effects of the two edge plasmons along the length and width directions. Under external magnetic field the two plasmonic resonances are respectively blue-shifted and red-shifted, leading to different dips in the vertical transmission spectrum through the graphene array. Following this mechanism, narrow-band and wider-band band-stop filters with dual stop bands are theoretically obtained in composite structures consisting of graphene sheet array layers and semiconductor substrate layer. The influence brought by structural parameters and the chemical potential of graphene on the filtering performance are analyzed. Numerical results show the center frequencies of the two stop bands of the filters can be efficiently tuned by the intensity of the magnetic field.

基于石墨烯的表面磁等离子体，提出了可磁调谐的太赫兹双带阻滤波器。石墨烯矩形片阵列的磁等离子体可归因于两个边缘等离子体沿长度和宽度方向的组合效应。在外部磁场下，两个等离子体共振分别发生蓝移和红移，从而导致通过石墨烯阵列的垂直透射光谱出现不同的下降。按照这种机制，理论上在由石墨烯片阵列层和半导体衬底层组成的复合结构中可以获得具有双阻带的窄带和宽带阻带滤波器。分析了结构参数和石墨烯的化学势对过滤性能的影响。