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arXiv · 2205.01250

First Principle Study for Optical Properties of TMDC/Graphene Heterostructures

Cheng-Hsien Yang·Shu-Tong Chang
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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.

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Cheng-Hsien Yang, Shu-Tong Chang. 2022-05-03. First Principle Study for Optical Properties of TMDC/Graphene Heterostructures. https://doi.org/10.3390/photonics9060387

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