First-principles study on the electronic structure and optical properties of GaAs nanowires

摘要

The electronic structure and optical properties of wurtzite gallium arsenide (GaAs) nanowires (NWs) are investigated within the first-principles plane-wave pseudo-potential method based on the density functional theory (DFT). The calculated results show that GaAs NWs are direct band gap semiconductor and demonstrate the achievement of p-type behavior. These NWs of the electronic behavior transitions from semiconductor to metal after hydrogen-passivated. The complex dielectric function, absorption coefficient and optical reflectivity are calculated and the peak position distributions of imaginary parts of the complex dielectric function have been explained. We may conclude GaAs NWs belongs to what crystal system through the dielectric tensors. Optical reflectivity is obtained and the peak position distributions of imaginary parts of the complex dielectric function have been explained, and their absorption spectra are sensitive to the large radius of GaAs NWs.