Strong Phonon-Plasmon Coupling in Grounded Graphene-Hexagonal Boron Nitride (hBN) Heterostructures

Abstract In this paper, an analytical model is proposed for a new graphene-based hexagonal Boron Nitride (hBN) heterostructure supporting tunable surface phonon-plasmon polaritons (SP3). The model is started with Maxwell’s equations and then applies boundary conditions. An exact dispersion relation is derived for the proposed structure in which the comparison between simulation and analytical results confirms its validity. A high value of FOM = 190 is reported for the chemical potential of 0.85 eV at the frequency of 48.3 THz. To further show the tunability of the structure, the influence of chemical potential and other geometrical parameters on the quality of propagating SP3 are investigated in detail. The authors believe that the presented study can be useful for the design of novel graphene-based devices in the THz region.