Reversible tuning the optical properties of defective TMDs monolayers

TL;DR

This paper demonstrates that applying strain to defective monolayer TMDs can reversibly modify their optical properties, offering a promising approach for tunable optoelectronic devices.

Contribution

It introduces a first-principles method to analyze how strain affects the optical absorption of defective TMD monolayers, highlighting reversible tuning capabilities.

Findings

Strain influences the absorption spectra of defective TMD monolayers.

Vacancy complexes enhance dipole matrix elements compared to simple vacancies.

Strain engineering enables reversible control of optical properties.

Abstract

Potential applications of monolayer of transition metal dichalcogenides (TMDs) in optoelectronic and flexible devices are under heavy investigation. Although TMDs monolayers are highly robust to external mechanical fields, their electronic structure is sensitive to compressive and tensile strain. Besides, intrinsic point defects are present in synthesized samples of these two dimensional (2D) materials which leads to the modification of their electronic and optical properties. Presence of vacancy complexes leads to absorption with larger dipole matrix elements in comparison to the case of simple transition metal vacancies. Using first principles calculations, we scrutinize the effect of various strain situations on the absorption spectra of such defective monolayers and show that strain engineering allows for reversible tuning of the optical properties.