The First Principles Study Of GaAs' Optical Properties And Electricity Properties

Gallium arsenide's good material characteristics make GaAs become the most important, most extensive use production and the largest amount of compound semiconductor materials. In this paper, based on the density functional theory within the framework of the first principles pseudopotential plane-wave method, the electronic structure, optical properties, elastic modulus as well as the electronic structure under stress are researched. The main contents of the study and its results are as follows:1,We have studied the bulk properties of the sphalerite GaAs, such as lattice parameters, band structure, bonding structure, density of state, and partial density of state. The calculated results indicate that GaAs is a direct wide band gap semiconductor material. However, the calculation of the band gap of GaAs is only 0.60eV, with the experimental value 1.43 eV has a larger deviation, the article analyzes the reasons for excessive devitation.2,The polarization matrix elements of the medium have been calculated, the energy loss spectra, the dielectric functions, reflectance spectra, refractive index and extinction coefficient and other parameters have been given. The calculated results also enable more precise monitoring and controlling during the growth of GaAs materials as possible.3,The electronic structure and optical properties of GaAs under strain have been calculated and the strain effects have also been studied. The band gap of GaAs is broadened with the increasing strain. The results indicate that Ga-As bond becomes shorter, and the valance bands shift towards the low energy while the conduction bands towards high energy with increasing strain. In addition, the peak in band is cracked slighted, the band gap turns wider and the Ga3d-As4p hybridization is enhanced. GaAs dielectric response to the transfer of high-frequency band, it can be considered to achieve to change the electrical properties of GaAs purpose of improving its scope of application, such as a mechanical sensor nm level through the imposition of external force. To provide a theoretical basis for the development of new types of GaAs photovoltaic materials.