闪锌矿MTe(M=Zn/Mg)的几何结构、弹性性质、电子结构和光学性质(英文)

Structural, Elastic, Electronic and Optical Properties of Zinc-Blende MTe(M=Zn/Mg)

采用基于密度泛函理论(DFT)框架下广义梯度近似(GGA)平面波超软赝势(PP-PW)方法,计算了闪锌矿型MTe(M=Zn/Mg)的几何结构、弹性性质、电子结构和光学性质.同时采用杂化密度泛函调准了带隙.结果表明,立方相ZnTe和MgTe均为直接带隙半导体材料.所得晶格参数、弹性常数及体模量与实验数据基本吻合.由弹性常数推导出ZnTe、MgTe的德拜温度分别为758、585K.研究了MTe的复介电函数、折射率、反射率和能量损失系数等光学性质,并基于电子能带结构和态密度对光学性质进行了解释.

The structural, elastic, electronic, and optical properties of zinc-blende MTe （M=Zn/Mg） compounds were studied. The ultrasoft pseudopotential plane wave （PP-PW） method, based on density functional theory （DFT） within generalized gradient approximation （GGA）, was used. Hybrid density functionals were applied to correct band gaps. Cubic ZnTe and MgTe are both direct band gap semiconductors, and calculated lattice parameters, elastic constants, and bulk moduli agree with previous results. Debye temperatures deduced from elastic constants for ZnTe and MgTe are 758 and 585 K, respectively. The dielectric function, refraction index, reflectivity and energy loss spectra were obtained and analyzed based on electronic band structures and densities of states.