First-Principles Study on the Effect of Strain on Single-Layer Molybdenum Disulfide

By adopting the first-principles plane wave pseudopotential method based on density functional theory, the electronic structure properties of single-layer MoS2 (molybdenum disulfide) crystals under biaxial strain are studied. The calculation results in this paper show that when a small strain is applied to a single-layer MoS2, its band structure changes from a direct band gap to an indirect band gap. As the strain increases, the energy band still maintains the characteristics of the indirect band gap, and the band gap shows a linear downward trend. Through further analysis of the density of states, sub-orbital density of states, thermodynamic parameters and Raman spectroscopy, it revealed the variation of single-layer MoS2 with strain. This provides a theoretical basis for realizing the strain regulation of MoS2.

Automated summary

This study investigated the electronic structure properties of single-layer MoS2 crystals under biaxial strain using density functional theory. Results showed a transition from direct to indirect band gap with small strain, maintaining characteristics of indirect band gap with increasing strain and linear decrease in band gap. Further analysis of density of states, sub-orbital density of states, thermodynamic parameters, and Raman spectroscopy revealed the strain-induced variations in single-layer MoS2, providing a theoretical basis for strain regulation of MoS2.