Sc掺杂SnO_(2)稀磁半导体的第一性原理研究

First-principles study of Sc-doped SnO_(2) dilute magnetic semiconductors

采用第一性原理方法,对Sc掺杂SnO_(2) 以及含有O空位的Sc掺杂SnO_(2) 的电子结构和磁学性质进行了计算. 结果表明SnO_(2) 晶格中存在两种本征磁性来源,分别为Sc掺杂诱导的未配对O-2p态电子的自旋极化和O空位诱导的未配对Sn-5p态电子的自旋极化. 由于两种未配对的弱束缚电子分别由电离施主和受主诱导产生,因此二者之间存在电荷补偿效应,在特定配比下能够使SnO_(2) 晶格出现磁性猝灭.

Based on first-principles, the electronic structures and magnetic properties of Sc doped SnO_(2) with and without O vacancy were calculated. Results show that there are two intrinsic magnetic sources in the SnO_(2) lattice, namely the spin polarization of unpaired O-2p state electrons induced by Sc doping and the spin polarization of unpaired Sn-5p state electrons induced by O vacancy. Since two kinds of unpaired weakly bound electrons are induced by ionizing donors and acceptors, respectively, there is a charge compensation effect between the two, and the SnO_(2) lattice can be magnetically quenched under specific Sc and vacancy ratios.