ZnSe和CuXSe_2(X=Al,Ga,In)结构和光学性质的研究

Study on the Structure and Optical Properties of ZnSe and CuXSe_2(X=Al,Ga,In)

利用赝势平面波基组的密度泛函理论方法,首先优化太阳能材料ZnSe和CuXSe_2(X=Al,Ga,In)的晶体结构,得到晶格参数、键长,并预测了CuXSe_2带隙和光学性质,带隙按照Al→Ga→In依次减小,但晶格参数和形变参数依次增加;通过光学性质中介电函数、吸收系数,反射率和光电导率分析发现,吸收系数的最强峰都在紫外区域,在3种晶体中光学性能按照Al→Ga→In依次增强。

The crystal structure of solar material ZnSe and CuXSe2（X = Al.Ga, in） has been optimized firstly by using the pseudopotential plane wave basis set of density functional theory, studied the lattice parameters, bond lengths, and forecasted the CuXSe2 band gap and optical properties. The results indicate that the band gap decreased in accordance with Al→Ga→In, but the lattice parameters and deformation parameters increased. The optical properties of dielectric function, absorption coefficient, reflectivity and photoconductive rate have been analised and foud that the strongest peaks of the absorption coefficient are in the ultraviolet region. The optical properties increased in accordance with Al→Ga→In successively in three crystals.