【摘要】 为了寻找新的高Tc的稀磁半导体(DMS),利用自旋局域密度泛函的第一性原理对 3d过渡金属(TM= V、Cr、Mn、Fe、Co或Ni)掺杂的II IV V2(CdGeP2 和ZnGeP2)以及I III VI2(CuGaS2 和CuGaSe2)黄铜矿半导体的电磁性质进行系统计算.结果发现:V或Cr 掺杂的 II IV V2 将出现铁磁(FM)状态,而 Mn、Fe或者 Co掺杂的 II IV V2 将出现反铁磁(AFM)状态,Ni掺杂时,DMS的磁性非常不稳定;在TM掺杂的 I III VI2 的DMS中,Cr、Mn掺杂的 CuGaS2 和 CuGaSe2将表现为FM状态,而当V、Fe、Co或Ni掺杂时,Cu(Ga,TM)S2 和Cu(Ga,TM)Se2 则表现了AFM性质.Cr掺杂的I IV V 以及 I III VI 黄铜矿半导体将可能出现较高的居里温度(Tc).更多还原

【Abstract】 In order to find new high-Tc diluted magnetic semiconductor （DMS）,a systematic study based on ab initio calculation is applied to material design of II-IV-V₂ （CdGeP₂ and ZnGeP₂） and I-III-VI₂ （CuGaS₂ and CuGaSe₂） chalcopyrite semiconductors doped by 3d-TM （TM=V,Cr,Mn,Fe,Co or Ni）.In II-IV-V₂-base DMS,the ferromagnetic （FM） state will be realized in V or Cr doped CdGeP₂ and ZnGeP₂,for Mn,Fe and Co doped ones,the antiferromagnetic （AFM） states are more stable than FM states,whereas Ni doped ones,the DMS magnetic state is not stable.In I-III-VI₂-base DMS,Cr or Mn doped CuGaS₂ and CuGaSe₂,DMSs will show FM state,whereas the other TMs doped,the DMSs show AFM state.II-IV-V₂ and I-III-VI₂ doped by Cr are good candidates for high-Tc DMSs.The calculated results accord well with a simple rule:when the t_2g orbitals of magnetic impurity are partially occupied,the DMS will show FM state;whereas when the t_2g orbitals of magnetic impurity are fully occupied or empty,the DMS will show AFM state.The simple rule can give us a start point to judge the magnetic stability for DMS.更多还原