Quantum Mechanical Calculations of the Dielectric Properties of Metallic 2D Transition Metal Dichalcogenides

2D materials are widely studied for their optical properties due to their reduced dimensionality. The key optical properties are reflectivity and absorption coefficients, which can be determined from the complex dielectric function obtained from first-principles quantum mechanical calculations based on time-dependent current-density functional theory (TDCDFT) [1]. Here we focus on the metallic phases of 2D transition metal dichalcogenides (TMD), including MoS2, MoSe2, and WSe2. We reveal their unique optical properties and discuss how the optical properties change upon the change of the chemical composition.

[1] G. Vignale, Phys. Rev. B. 70, 201102R (2004).