Mn掺杂ZnO纳米线磁性质的第一性原理研究

本文采用第一性原理方法系统研究了Mn原子单掺杂和双掺杂ZnO纳米线的稳定性和磁性质.所有掺杂纳米线的束缚能都为负值,表明掺杂增强了纳米线的稳定性.表面掺杂纳米线显示了直接带隙半导体特性,而中间掺杂纳米线显示了间接带隙半导体特性.纳米线的总磁矩主要来源于Mn原子3d轨道的贡献.由于杂化,相邻的O原子和Zn原子也产生了少量自旋.在超原胞内,Mn原子和O原子磁矩平行排列,表明它们之间是铁磁耦合.

Magnetic properties of Mn-doped ZnO nanowires studied by first-principles calculation

The stabilities and magnetic properties of ZnO nanowires doped with one and two Mn atoms are comparatively studied in terms of the first-principles calculation. The formation energies of doped nanowires are smaller than that of the pristine one, indicating that the doing process enhances the stability of nanowires. Surface doped nanowire showed semiconducting characteristics with direct band gap, whereas the intermediate doped nanowire showed semiconducting characteristics with indirect band gap. The magnetic moments are mainly contributed by the Mn-3d orbital. Due to the hybridization interaction, a small magnetic moment is also induced in nearest neighboring O and Zn atoms. The magnetic moments of the Mn and O atoms have the same direction, indicating ferromagnetic coupling between them.