Theoretical Investigation of Adjustable Plasmonic Modes in Graphene- based Heterostructures in THz Range: Transfer Matrix Method

Abstract

Abstract In this article, we investigate the characteristics of the reflected beam from graphene-based hexagonal Boron Nitride (hBN) heterostructure. Analytical expressions are obtained for calculating the reflection characteristics. A large value of the reflected group delay is reported in the lower Reststrahlen band; therefore, this frequency range is chosen to be studied. To show the tunability of the proposed structure, the variations of the reflected beam as a function of frequency are depicted and studied for various values of chemical potential. Our results indicate a large value of the reflected group delay, i.e. 𝝉r = 15.3 ps, at the frequency of 24.9 THz. Moreover, we will show that the thickness of graphene sheets, the hBN medium, and the SiO2 layer can change the quality of the reflected beam more effectively. The authors believe that the presented study can be utilized for the design of optical delay structures in the mid-infrared region.