Band nesting and the optical response of two-dimensional semiconducting transition metal dichalcogenides

TL;DR

This study uses ab-initio DFT to analyze how band nesting and van Hove singularities in 2D transition metal dichalcogenides lead to strong optical responses, highlighting their potential for photon-electron interactions.

Contribution

It reveals the significant role of band nesting and van Hove singularities in enhancing optical conductivity in 2D STMDCs, providing insights into their optoelectronic properties.

Findings

Large optical response due to band nesting

Enhanced nesting from van Hove singularities

Strong photon-electron interactions possible in 2D

Abstract

We have studied the optical conductivity of two-dimensional (2D) semiconducting transition metal dichalcogenides (STMDC) using ab-initio density functional theory (DFT). We find that this class of materials presents large optical response due to the phenomenon of band nesting. The tendency towards band nesting is enhanced by the presence of van Hove singularities in the band structure of these materials. Given that 2D crystals are atomically thin and naturally transparent, our results show that it is possible to have strong photon-electron interactions even in 2D