碳掺杂BaTiO_3的电子结构和磁性研究

Electronic structure and magnetic properties in C-doped BaTiO_3:A first-principles calculations

基于密度泛函理论,从头计算了C间隙和替位氧掺杂立方结构BaTiO3的电子结构和磁学性质.结果表明C掺杂BaTiO3在自旋极化状态下的总能量比自旋非极化状态下的总能量小,说明C掺杂BaTiO3的基态具有铁磁性.从态密度和自旋电子密度分布可知,C位于BaTiO3间隙的磁性机理和过渡金属掺杂半导体产生磁性的机理类似;C替位掺杂BaTiO3体系磁性源于未配对的C2p电子.

Based on density functional theory calculations, the electronic structure and magnetic properties of C-doped BaTiO3 are inves- tigated. It is found that the BaTiOa doped by a nonmagnetic 2p light element （C） is ferromagnetic. The local magnetic moment is mainly localized on doped C atoms for Csub, while ferromagnetism in Cins comes from precipitation of magnetic ions Ti3＋. Our re- sults indicate that the proposed C-doped BaTiO3 is a potential candidate for dilute magnetic semiconductor material and multiferroics material.