First Principle Study for Optical Properties of TMDC/Graphene Heterostructures

TL;DR

This study uses first-principles calculations to analyze the electronic and optical properties of TMDC/Graphene heterostructures, revealing their potential for optoelectronic applications through detailed property comparisons.

Contribution

It provides a theoretical investigation of four TMDC/Graphene heterostructures using DFT, focusing on their electronic and optical characteristics for the first time.

Findings

Comparison of complex permittivity, absorption, reflectivity, and refractive index.

Identification of optical property variations among different heterostructures.

Insights into potential optoelectronic applications of TMDC/Graphene heterostructures.

Abstract

The transition-metal dichalcogenide (TMDC) in the family of $\mathrm{MX}_2$ ($\mathrm{M}=\mathrm{Mo},\mathrm{W}$; $\mathrm{X}=\mathrm{S},\mathrm{Se}$) and the graphene monolayer are atomically thin semiconductors and semimetal, respectively. The monolayer $\mathrm{MX}_2$ have been discovered as a new class of semiconductors for electronics and optoelectronics applications. Because of the hexagonal lattice structure of both the materials, $\mathrm{MX}_2$ and graphene are often combined with each other to make van der Waals heterostructures. Here, the $\mathrm{MX}_2/\mathrm{Gr}$ heterostructures are investigated theoretically based on the Density Functional Theory (DFT). The electronic structure and the optical properties of four different $\mathrm{MX}_2/\mathrm{Gr}$ heterostructures are computed. We systematically compare these $\mathrm{MX}_2/\mathrm{Gr}$ heterostructures for their complex permittivity, absorption coefficient, reflectivity and refractive index.