【摘要】 基于密度泛函理论的赝势平面波方法计算了处于填隙位置磁性原子 (MnI)对 (Ga ,Mn)As体系电子结构和磁性的影响 .计算结果表明MnI 在GaAs中是施主 ;代替Ga位的MnGa 与MnI 的自旋按反铁磁序排列 ;静电相互作用使MnGa,MnI 倾向于形成MnGa_MnI 对 .MnI 的存在一方面补偿了 (Ga ,Mn)As中的空穴 ,降低了空穴浓度 ;同时还使邻近的MnGa失活 .MnI 的存在对获得高居里温度的 (Ga ,Mn)As是极为不利的更多还原

【Abstract】 The effects of interstitial Mn （Mn_I） atoms on the electronic and magnetic properties of （Ga,Mn） As are studied within the pseudopotential plane_wave frame work based on the density functional theory. Numerical results show that Mn_I atoms are donors in GaAs. The Mn atoms that substitute for Ga sublattices (Mn_Ga) and Mn_I are antiferromagnetically coupled. The static electrical interaction makes the Mn_Ga and Mn_I atoms tend to form Mn_GaMn_I pairs. The Mn_I atoms not only compensate the holes, and reduce the hole density of （Ga,Mn）As, but also deactivate Mn_Ga atoms. The existence of Mn_I atoms are very disadvantageous for obtaining （Ga,Mn）As samples having high Curie temperatures.更多还原