Biaxial tensile-compressive deformation on the electronic structure and optical properties of doped with different concentrations F–MoTe2: A first-principles study

Under the framework of density functional theory based on the first principles, the plane wave pseudopotential method was used to investigate the effects of biaxial stretch-compression deformation on the electrical structure and optical characteristics of molybdenum telluride systems doped with various fluorine atom concentrations. Electrical structure, density of states, charge transfer, and optical characteristics were calculated and thoroughly investigated in the molybdenum ditelluride system. The results demonstrate that the band gap shrinks with increasing fluorine atom doping concentration of fluorine atoms, and n-type doping occurs for different doping concentrations of halogen fluorine atoms. The semiconductor-quasi-metal transition occurs in the MoTe2 system when the doping concentration reaches 16.67%. After that, the fluorine atoms with 4% doping concentration were deformed by stretching and compression, and the semiconductor started to transition to quasi-metal as the amount of stretching increased. The deformation of the system changed considerably when the stretching amount was 14%. Compression induces a direct-to-indirect bandgap transition, transforming semiconductors into metals. Significant changes in electronic energy band diagrams and density of states diagrams. In terms of optical qualities, the absorption spectra of the entire system are blue-shifted during stretching and compression. The reflectance spectra are red-shifted and then blue-shifted.