Electronic and optical properties of molybdenum disulfide (MoS2) mono layer using density functional theory (DFT) calculations

This work presents a detailed computational study of the electronic and optical properties of monolayer MoS2, focusing on its potential for optoelectronic and quantum applications. This study employs first-principles calculations based on density functional theory and time-dependent density functional perturbation theory (TDDFPT) to investigate the material’s band structure, projected density of states (PDOS), absorption spectrum, dielectric function, and joint density of states (JDOS). The direct bandgap at the K-point, as revealed by the band structure, highlights MoS2’s suitability for high-efficiency photodetectors and light-emitting devices. The PDOS and absorption spectrum confirm the dominant role of Mo-d and S-p orbitals in shaping the conduction and valence bands, respectively, with the absorption peak at 0.94 eV aligning with experimental observations. The dielectric function reveals a smooth transition from transparency to refractivity at higher photon energies, supporting its potential in photonic and integrated circuit applications. In addition, the JDOS shows selective optical transitions, suggesting MoS2’s promise for UV detection and high-energy light emitters. These findings establish monolayer MoS2 as a versatile material with significant promise for future optoelectronic systems and quantum computing applications.