La2O2S电子结构及光学性质的第一原理研究

Research on Electronic Structure and Optical Properties of La_2_O2S Using First-principles Method

基于密度泛函理论的第一原理方法研究了La2O2S的电子结构及光学性质。能带结构分析表明:La2O2S是一种间接带隙的半导体材料,价带顶和导带底分别位于A点和K点。对带隙剪刀修正后,也通过第一原理方法研究了La2O2S的光学性质。计算并分析了La2O2S介电函数的虚部、实部以及由它们所派生的光学常数,即折射率、消光系数、反射率、吸收系数和透光率等。

The electronic structure and optical properties of La2O2S are investigated using the first principles method based on the density-functional theory. The analysis of band structure suggests that La2O2 S is an indirect semiconductor with the conduction band minimum and the valence band maximum locating at K point and A point, respectively. The optical properties of La2O2S are also investigated by first-principles after the band gap scissor correction. The real and imaginary parts of the complex dielectric function and derived optical constants, viz. , the refractive index, extinction coefficient, reflectivity, absorption coefficient and transmittance are calculated and analyzed.