Circuit modeling of tunable terahertz graphene absorber

Abstract

In this work an efficient circuit model of functional thin-film graphene assisted metamaterial (GM) devices with exploiting transmission line theory (TLT) is presented. In our proposed model, graphene sheet layer considered as parallel R-L-C circuits and the other parts of the devices modeled as circuit elements. Here we develop the structure and design multi-layer unpattern GM absorber. To evaluate robustness, performance and accuracy of our developed TLT method, the results obtained from an easy to implement MATLAB code for a GM absorber have been compared with those obtained from full-wave simulations and analytical approach. Our proposed method in addition to reducing the calculation time and the need for less memory compared to full-wave simulations, is in good agreement with the full-wave and analytical simulations (with an error less than 3%). By changing chemical potential and/or dielectric thickness of the GM absorber, the absorption peek’s frequency could be tuned in terahertz band as desired, indicating the potential applications of the absorber in sensors and filters.