Electrodynamic calculation of a complex coefficient of electromagnetic wave propagation in the waveguiding structure “carbon nanotube - graphene” in terahertz and infrared ranges

Optical, electronic and mechanic properties for developing of waveguiding 2D structures and graphene-based devices at terahertz (THz) and infrared (IR) frequency ranges. The aim of the present work is to theoretically research propagation of electromagnetic waves in novel waveguiding 2D structures based on CNT- graphene at THz and near IR frequencies using mathematical modeling by solving the Maxwell's equations, complemented by the constitutive laws for CNTs and graphene. Materials and methods. A mathematical model of propagation and interaction of electromagnetic waves in waveguiding 2D structures based on CNT- graphene was developed by solving the Maxwell boundary value problem, where the graphene electron surface conductivity is included as a parameter and determined from the Kubo formalism, using a computational algorithm on autonomous blocks with Floquet channels (FABs). Results. The results of electrodynamic calculation of the real and imaginary parts of complex wave numbers and coefficients of delay and extinction of the fundamental mode in waveguiding 2D structures based on CNT- graphene depending on the frequency were obtained for different values of the chemical potential (the external electric field intensity) at THz and near IR frequency ranges. Conclusions. It is shown that the dispersion performances of electromagnetic waves in waveguiding 2D structures based on CNT- graphene depend on the geometry sizes ( the CNT radius and the distance between CNT and graphene) and can be tuned by the external electric field at THz and near IR frequencies.