Tunable attenuator based on hybrid graphene-black phosphorus microstrip line for terahertz applications

Abstract This paper presents a novel type of tunable attenuator based on hybrid graphene-black phosphorus microstrip line for terahertz applications. Two configurations are studied, the first is composed of a metal microstrip line and one or two graphene sheets, and in the second a BP sheet is placed under the graphene. A transverse equivalent network is proposed to offer the general understanding of the attenuation mechanism. The simulated result shows a strong agreement between the WCIP method and CST simulator, which confirms the accuracy of the algorithm developed by the WCIP method for the graphene, BP and hybrid area. The results suggest that the attenuator with two graphene sheets gives a wider tunable attenuation range when compared with the attenuator with one graphene sheet at only one side. Furthermore, by putting the graphene on the BP, the attenuation tuning range has been enhanced, where it increases from 2.10–23.96 dB to 3.85–31.69 dB.