Uniaxial strain-induced electronic property alterations of MoS2 monolayer

Abstract

Molybdenum disulfide (MoS2) has attracted interests owing to its strain-tuned electronic and optical properties, making it a promising candidate for applications in strain engineering devices. In this study, we investigate the effect of uniaxial strain on the electronic properties of MoS2 monolayer using first-principles calculations. Results show that a crossover of the K–K direct to Γ–K indirect bandgap transitions occurs at a strain of 1.743%. Moreover, a strong correlation is observed between the modified bandgap and the density of states (DOS) of the Mo–4d and S-3p orbitals at the valence band maximum and conduction band minimum. The uniaxial strain–tuned interatomic distance along the a-crystallographic axis not only alters the bandgap at different rates but also affects the DOS of the Mo–4d orbital and possible electronic transitions. This study clarifies the mechanism of the electronic structural modification of two-dimensional MoS2 monolayer, which may affect intervalley transitions.