The Study Of Electronic Structure And Optical Properties Of InGaNAs Material

As one of important optoelectronic materials, InGaNAs has been applied in the manufacture of the manufacture of GaAsSb/InGaNAs/ GaAs trilayer quantum-well laser. This material has showed its potential candidate in the field of near infrared detector and quantum-dot semiconductor optical amplifiers. In this thesis, the geometry configuration, electronic structure and optical properties of GaAs/ InGaAs/InGaNAs are investigated based on first-principles in the framework of Density Functional Theory (DFT). As a typical V element, SnO2 doped with antimony are also simulated. The main contents of this thesis are summarized as follows:1. After a series of simulation with different schemes, LDA (CA-PZ) is chosed for intrinsic GaAs and its doping configurations.2. The electronic structure changes of InxGa1-xAs/InxGa1-xNyAs1-y with varying doping concentration are investigated. The corresponding energy band structures and partial density of states (PDOS) are discussed in detail in order to reveal the relationship between these properties.3. The imaginary part of dielectric functionε2(ω) is introduced as the primary parameter in optical properties. Absorption coefficient a(ω), energyloss spectrum L(ω), reflectivity R(ω) and refractive index n(ω) are discussed successively. The optical transition of In dopant in GaAs exhibits a red shift, while the N dopant in InGaAs shows a blue shift. Moreover, the relation between the spectrum information and electronic structure are discussed.4. Finally, Sb-doped SnO2 are studied in order to predict its change in electronic structure and optical properties.