Fundamental effect of strain on carrier mobility in monolayer MoS2.

First-principles calculations are used to comparatively reveal the fundamental effects of tensile strain on the effective mass, deformation potential, and carrier mobility of monolayer MoS2. It is found that the hole mobility is higher than that of electrons in unstrained monolayer MoS2, and applying tensile strain is shown to reverse the dominant carrier polarity from holes to electrons. In the case of uniaxial loading, the electron mobility enhancement stems from a simultaneous reduction in both the effective mass and the deformation potential. Under biaxial strain, however, the improvement is predominantly driven by a substantial drop in the deformation potential. Calculations also reveal that biaxial strain proves markedly more effective in boosting carrier mobility than its uniaxial counterpart. The present results align closely with experimental observations, and provide a deep understanding of the fundamental effects of uniaxial and biaxial tensile strain on carrier mobility of monolayer MoS2.