Uniaxial strain-induced electronic property alterations of MoS2 monolayer

The MoS2 has attached interest due to its strained tuned electronic and optical properties which open promising application in strain engineering devices. In this study, we investigate the uniaxial strain effect on the electronic properties of MoS2 monolayer by first-principles calculations. Our calculation shows the crossover of the K ― K direct to  ―K indirect transition occurs at a strain of 1.743%. In addition, we also observed a strong correlation between bandgap modification and the density of states (DOS) of Mo-4𝑑 and S-3𝑝 at valence band maximum and conduction band minimum. We propose that the interatomic distance modified by the uniaxial strain along 𝑎-axis does not only create different rates of bandgap alteration but also affects the Mo-4𝑑 DOS and possible electronic transitions. This study points to the mechanism behind the electronic structure modification of two-dimensional MoS2 monolayer, which might have important implication on intervalley transitions.