Outstanding tunable electrical and optical characteristics in monolayer silicene at high terahertz frequencies

Abstract

Silicene, a zero-bandgap semimetallic advanced material, has received much attention due to its extraordinary electronic and optical characteristics, enabling its use in plasmonic nano-devices. This material is able to be tuned without degrading its high carrier mobility. In this work, by applying rigorous numerical techniques, the optical and electrical properties of silicene at high terahertz frequencies are calculated. Under the influence of environmental effects including the Fermi level, temperature, and external electric field, the optical conductivity and refractive index of silicene are investigated using the tight-binding model. The effects of the Fermi level from 0 to 1 eV, the external electric field from 0 to 2.5 \({\text{V}}/{\dot{\text{A}}}\), and temperature from 5 to 400 K are investigated with respect to the optical properties of silicene. One of the interesting features of silicene is its adjustable bandgap, which we present here.