Strain tunable electronic states of MoSe2 monolayer

Highlights: • MoSe₂ monolayer can tolerate a large range of elastic strain. • Strain engineering is an effective approach to modulate the band structure of MoSe₂ monolayer. • The strained MoSe₂ monolayer still maintains the semiconductor property. First-principles calculations were carried out to study the influence of strain on the electronic structure of MoSe₂ monolayer. Both uniaxial and biaxial strain were taken into consideration, and our calculations reveal that MoSe₂ monolayer can tolerate a large range of elastic strain. More importantly, the electronic structure of MoSe₂ monolayer can be significantly tuned by strain, which is attributed to the redistribution of Mo 4d and Se 4p orbitals. However, the strained MoSe₂ monolayer still maintains the semiconductor properties, although its bandgap undergoes a transition from direct to indirect over a certain amount of strain.