采用全电势线性缀加平面波(FP-LAPW)方法,计算一层与两层Fe原子替代Sn原子的超晶格SnO2的电子态密度和各项光学参数。计算结果表明:掺Fe后材料均属于直接跃迁半导体,且呈现半金属性;随着掺杂层数的增加,费米能级进入价带,带隙逐渐减小,Fe原子之间耦合作用增强;吸收谱、消光系数等均与介电函数虚部谱线相对应,且均发生红移,吸收系数的吸收边随掺杂层数的增多而逐渐减小,各光学谱线随掺杂层数的增多在高能区的峰值明显降低。
Using the full potential linearized augmented plane wave method (FP-LAPW), we present the electronic structure and multi-optical properties of Fe-doped SnO2 superlattices. The results reveal that the doped system belongs to direct-gap semi-conductor and has half-metallic ferromagnetic properties;The Fermi energy levels move to the valence band, the band gap decreases with the increase of doping concentration, and the coupling effect among Fe atoms is strengthened ;The absorption spectra and energy loss spectra all correspond to the imaginary part of the epsilon spectrum and have spectral red shift, and the optical absorption edges and the peak value of optical spectra in high energy range decrease with the increase of doping concentration.