N掺杂锐钛矿TiO_2光学性能的第一性原理研究

First-principles study the optical properties of anatase TiO_2 by N-doping

用平面波赝势方法(PWP)计算了N掺杂锐钛矿型TiO2前后的光学特性,即介电函数虚部ε2(ω),光学吸收系数I(ω)和反射率R(ω).并从能带结构上解释了为什么掺N后锐钛矿型TiO2的光学谱在2.93,3.56和3.97eV处相对掺杂前会出现3个峰值的原因.从光谱图上分析得出,掺杂后TiO2要发生红移现象,实验现象证实了这一结果.

We have calculated the optical properties of anatase TiO2 and anatase TiO2 by N-doping by plane-wave pseudo-potential method （PWP）, namely the imaginary part of dielectric function-ε2 （ω）, the optical absorption coefficient 1 （ω） and the reflectivity R（ω）. We have given an explanation in terms of band structures why the optical spectrum has three main peaks around 2.93 eV,3.56 eV and 3.97 eV after N-doping. Our studies of the optical spectra show that the Red-shift will happen after N-doping, and experimental phenomena also approve the result.