不同浓度Mn掺杂LiMgN新型稀磁半导体的磁电性质  

Magnetoelectric properties of new diluted magnetic semiconductor LiMgN with different concentrations of Mn doping

作　　者：杜成旭 徐建 陈婷 庞星星 刘洋华 毋志民 

机构地区：[1]重庆师范大学物理与电子工程学院光电功能材料重庆市重点实验室,重庆401331

出　　处：《功能材料》2018年第2期2097-2102,共6页Journal of Functional Materials

基　　金：重庆市基础与前沿研究计划资助项目(cstc2014jcyjA50005);重庆师范大学教学名师培育计划资助项目(02030307-0003);重庆科技学院院士专家重点实验室合作资助项目(CQKL-1505);重庆高校创新团队计划资助项目(CXTDX201601016);重庆市研究生科研创新资助项目(CYS17179);大学生创新创业训练计划资助项目(201610637012;201610637103)

摘　　要：采用基于密度泛函理论的第一性原理平面波超软赝势方法,对纯LiMgN、不同浓度Mn掺杂LiMgN及Li不足和过量时不同浓度Mn掺杂LiMgN的超晶胞进行几何优化,计算并分析它们的电子结构、半金属性和磁电性质。结果表明,Li1±y(Mg1-xMnx)N(x,y=0.0625,x,y=0.125)体系均表现为100%自旋注入,材料均具有半金属性;Mn单掺LiMgN时,随着Mn浓度的增加,杂质带宽度增大,居里温度提高;Li不足时,随着Mn浓度的增加,体系带隙值减小,导电能力增强;Li过量时,当Mn浓度为6.25%时,杂质带宽度和半金属能隙最大,带隙值最小,体系的居里温度提高。说明Mn掺杂LiMgN体系可以通过改变Mn的浓度和调节Li的含量来实现磁性和电性的分离调控。Using first-principles density functional theory based on the full potential linearized augmented plane wave method and generalized gradient approximation(GGA),the geometric structures of pure LiMgN,different concentrations of Mn-doped LiMgN,and different concentrations of Mn-doped LiMgN with either excess Li or Li deficiency are optimized,and their electronic structures,half-metallic properties and magnetoelectric properties are calculated.The results show that in the systems of Li1±y(Mg1-xMnx)N(x,y=0.0625,x,y=0.125),a100% spin injectors is revealed,and the materials exhibit half metallic.When Mn is doping LiMgN,the width of impurity band and Curie temperature increased with the increase of Mn concentration.In the Li-deficiency compounds,with the increase of Mn concentration,band gap value of system decreases and the conductive capability increased.In the Li-excess compounds,impurity band width and semimetal energy gap are the largest,which can realize to improve the Curie temperature of Mn doping LiMgN system,while band gap achieves the minimum value at 6.25% Mn concentration.It indicates that Mn doping LiMgN system can be regulated by changing the concentration of Mn and the content of Li to implement electrical and magnetic control.

关 键 词：Mn掺杂LiMgN 电子结构 铁磁性 第一性原理 

分 类 号：TB34[一般工业技术—材料科学与工程]