CaO掺立方ZrO_2对其高压电子结构和光学性质影响

Effects of CaO-Doping in Cubic Zirconia on Its Electronic Structure and Optical Properties at High Pressure

基于密度泛函理论框架下的第一性原理平面波超软赝势方法并结合广义梯度近似(GGA),分别计算了60 GPa压力下立方氧化锆理想晶体以及在其中掺CaO时的电子结构和光学性质.结果表明,CaO的掺入使得立方氧化锆的能隙减小了约0.62 eV,其吸收边有微小红移.但在60 GPa的冲击压力下,掺杂不会影响立方氧化锆在可见光范围内的高压光吸收性,立方氧化锆理想晶体以及在其中掺入CaO时均在可见光区保持良好的透明性.立方氧化锆中掺入CaO将使得约105 nm处的反射谱主峰发生微小红移,峰值强度略有降低,同时,也导致103 nm左右的能量损失谱主峰略红移,且峰值强度显著降低.

Based on the density functional theory, the first-principle ultra-soft pseudo-potential method was used in combination with generalized gradient approximation （GGA） to calculate the electronic structure and optical properties of perfect cubic ZrO2 at 60 GPa with or without CaO doping. The results showed that CaO doping decreased the band gap of the cubic ZrO2 by approximately 0.62 eV, inducing a small red- shift of the absorption edge. However, at a shock pressure of 60 GPa, the optical absorption of cubic zirco- nia in the visible-light region was not influenced by CaO doping, and the perfect CaO-doped cubic ZrOz re- mained well transparent in the visible-light region. In addition, CaO-doping in cubic ZrO2 caused a small red-shift and a slight intensity decrease for the reflectivity spectrum peak at about 105 nm and led to a tiny red-shift and an obvious intensity decrease for the loss-function spectrum peak at about 103 nm.