CdSx Se1－x合金结构、电子结构和光学性质的第一性原理研究

摘要

用密度泛函理论究了闪锌矿型三元合金体系CdSx Se1－x的晶体结构、电子结构和光学性质。计算了组分参数在0≤x≤1范围内CdSx Se1－x的电子结构、态密度和带隙，计算结果表明CdSx Se1－x为直接带隙半导体材料，其带隙随Se含量的增加而减小。分析了CdSx Se1－x的复介电函数和吸收系数等光学性质随光子能量变化的关系，随Se元素含量增加，各光学特性曲线向低能方向移动。%The electronic structure, electronic and optical properties of CdSx Se1 -x alloys were studied using the first-principles calculations based on the density functional theory ( DFT) .Electronic structure, density of states and energy bandgap for CdSx Se1-x were estimated in the range 0≤x≤1.It is observed that the direct bandgap Eg of CdSx Se1-x decreases with the increase of Se content.Furthermore, results for complex dielectric constants and absorption coefficients were also described.All optical characteristic curves of CdSx Se1-x slightly shift to low energy with the increase of Se content.