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基于广义梯度近似平面电子波函数密度泛函理论计算的方法研究了无压力下和在1 GPa外压应力下闪锌矿结构ZnS的能带结构、电子状态密度、结合状况和介电性能。结果表明在外加1 GPa压力时闪锌矿结构ZnS晶格常数由2.7605减小到2.7049,对称性不变.在外压1 GPa应力下ZnS仍呈直接带隙的能带结构,带隙宽度较未加压力时减小到1.698 e V.在外加1 GPa压应力下ZnS费米能附近的载流子浓度大大增加,更容易发生跃迁而产生电迁移和光电现象。外加1 GPa压力时Zn-S键长由2.3905减小到2.3405,Zn-S成键数量由1.820个增加到1.860个.ZnS硫化物在紫外和可见光波段主要存在四个介电吸收峰,外加1 GPa压应力下位于170 nm和210 nm附近的直接跃迁介电吸收峰强度降低.
The band structure, electron density, bonding state and dielectric properties of zinc sphalerite ZnS under pressureless and under 1 GPa external pressure were studied based on the generalized gradient approximation of planar electron wave function density functional theory. The results show that the lattice constant of ZnS in sphalerite decreases from 2.7605 to 2.7049 at 1 GPa pressure, and the symmetry is unchanged.The band gap of ZnS is still directly bandgap at 1 GPa of external pressure, Which is 1.698 eV lower than that of the unpressurized one. With the increase of the compressive stress of 1 GPa, the concentration of ZnS near Fermi energy is greatly increased, and the transition occurs more easily, resulting in electromigration and photoelectric phenomena. The Zn-S bond length decreases from 2.3905 to 2.3405 and the number of Zn-S bonds increases from 1.820 to 1.860 at 1 GPa pressure.ZnS sulfide mainly has four dielectric absorption peaks in the UV and visible region, In addition, the intensity of the direct transition dielectric absorption peak at 170 nm and 210 nm under 1 GPa compressive stress decreases.