Investigation of plasmonic properties of graphene nanoribbon waveguide on hBN and substrate in the MID-IR spectrum range

In this study, waveguide properties of graphene nanoribbon on hBN and a substrate were investigated. Precisely, the plasmonic mode properties including real part of refractive index, propagation length, and figure-of-merit (FoM) on frequency, Fermi energy of graphene, and substrate in the mid-IR spectrum range were inspected. The simulated results show that graphene waveguide is intensively sensitive to the frequency, Fermi energy and structural geometry in the mid-IR range. Also, the propagation length for a Fermi energy of 0.3 (0.9) eV in the frequency range of 1375 cm-1 to 1600 cm-1 reachs from 0.1 (0.4) to 0.38 (4.15) µm, where shows a 3 (10) fold enhancement.