Quasiparticle band structures and optical properties of strained monolayer MoS 2 and WS 2

By Hongliang Shi, H. Pan, Yong-Wei Zhang, Boris I. Yakobson. 2012

697 citations recorded by the source corpus.

The quasiparticle (QP) band structures of both strainless and strained monolayer MoS$_{2}$ are investigated using more accurate many body perturbation \emph{GW} theory and maximally localized Wannier functions (MLWFs) approach. By solving the Bethe-Salpeter equation (BSE) including excitonic effects on top of the partially self-consistent \emph{GW$_{0}$} (sc\emph{GW$_{0}$}) calculation, the predicted optical gap magnitude is in a good agreement with available experimental data. With increasing strain, the exciton binding energy is nearly unchanged, while optical gap is reduced significantly. The sc\emph{GW$_{0}$} and BSE calculations are also performed on monolayer WS$_{2}$, similar characteristics are predicted and WS$_{2}$ possesses the lightest effective mass at the same strain among monolayers Mo(S,Se) and W(S,Se). Our results also show that the electron effective mass decreases as the tensile strain increases, resulting in an enhanced carrier mobility. The present calculation results suggest a viable route to tune the electronic properties of monolayer transition-metal dichalcogenides (TMDs) using strain engineering for potential applications in high performance electronic devices.

Subfields: Electrical and Electronic Engineering, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/90d2d72b89632d352b9ce10449169ec639acb10a

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Electrical and Electronic Engineering

In Materials Chemistry

Citations in the corpus

Strain-engineered high-responsivity MoTe2 photodetector for silicon photonic integrated circuits (2019, methodology): “rain. A straightforward method to achieve strain in 2D nanocrystals is through mechanical bending, such as transferring them onto flexible substrates or wrapping them around a pre-patterned structure [6, 7, 8, 9]. Under small (<2%) compressive (tensile) strain, the bandgap increases (decreases) a”
A Comparative Study of Electronic Properties of Bulk MoS2 and Its Monolayer Using DFT Technique: Application of Mechanical Strain on MoS2 Monolayer (2014, background): “Moreover, at strains larger than 1% the lowest lying band gap changes from direct to indirect [19]-[22].”
Few-layer MoS2: a promising layered semiconductor. (2014, background): “org E Band structure redesign under tensile strain is predicted to lower the electron effective mass and consequently improve electron mobility.(124) Applied strain could also cause band degeneracy which can be used for better spin-related properties and research in MoS2.”