Fe,Mn共掺SnO_2超晶格电子结构和光学性质研究  

Study on Electronic Structure and Optical Properties of Fe and Mn Codoped SnO_2 Superlattice

作　　者：王喆[1] 逯瑶[1] 王培吉[1] 

机构地区：[1]济南大学物理科学与技术学院,济南250022

出　　处：《人工晶体学报》2013年第7期1429-1434,1439,共7页Journal of Synthetic Crystals

基　　金：国家自然科学基金(61172028);山东省自然科学基金(ZR2010EL017)

摘　　要：基于密度泛函理论的第一性原理,采用了广义梯度近似(GGA)处理交换相关势,用Wien2k软件计算了SnO2超晶格掺杂单层Mn、双层Mn及Fe、Mn共掺情况下的态密度、能带结构、光学性质。结果表明SnO2超晶格单掺Mn时,材料表现为半金属性,这是由于Mn-3d与O-2p的耦合作用,而双层Mn掺杂时仅有O-2p提供。随Mn掺杂层数的增加,其光学性质在低能级处的峰值增大,光学吸收边发生红移,材料透光性能增强。当Fe、Mn共掺时,态密度向低能方向移动,能带结构在Fermi能级附近出现自旋极化,材料表现为半金属性,这是由于Fe与Mn强烈耦合所致。材料的吸收谱、反射谱、能量损失图谱变化趋势一致,但共掺杂比单掺时各谱更向低能方向移动。Using first-principles full potential linearized augmented plane wave method（FP-LAPW）,the total density of states（DOS）,energy structure and optical properties of Mn-doped and Mn and Fe codoped in SnO2 superlattices by Wien2k were presented.The results showed that due to the one-layer Mn doping,SnO2 superlattices shows half-metallic,which is contributed by Mn-3d and O-2p.But for two-layer Mn doping,it is contributed by O-2p only.As the concentration increasing,the sharp peaks are found in the low energy area.The optical absorption edges decreased as the doping concentrations increasing,and the light-admitting quality of system is enhanced.The DOS moves to low-energy area.Due to the strong coupling between Mn and Fe,the system shows half-metallic character and spinpolarized nearby the Fermi level.Absorption,refraction and energy loss spectrum have the same changing trend.Compared to the system of Mn-doped SnO2,the Mn-Fe-codoped SnO2 systems move to lower energy area.

关 键 词：SnO2超晶格 态密度 电子结构 光学性质 第一性原理 

分 类 号：O472.3[理学—半导体物理]