采用自旋极化密度泛函理论方法对Co掺杂闪锌矿ZnO的能带结构、态密度、磁学和光学属性进行了研究。计算结果显示: Co掺杂闪锌矿ZnO的基态是反铁磁态, 具有金属性特征; 而铁磁态具有半金属性特征。铁磁耦合在费米能级附近出现了明显的自旋劈裂现象, 表现出明显的不对称性和强烈的Co 3d和O 2p 杂化效应。磁矩主要来源于Co 3d轨道电子以及部分近邻耦合的O 2p轨道电子, 大小与Co原子的掺杂位置有关。光学性质计算结果显示, Co掺杂闪锌矿ZnO在可见光范围内都有较强的光吸收能力, 吸收峰在高能区发生了红移现象。理论计算结果表明, Co掺杂闪锌矿ZnO或许是一种优异的磁光材料。

The band structure, density of state, magnetic and optical properties of Co doped zinc blende ZnO were systematically studied by using the first-principles based on the spin polarized density functional theory. The calculated results show that the ground state of Co doped zinc blende ZnO is antiferromagnetic and shows metal characteristics, while the ferromagnetic state shows the half-metallic characteristics. For the ferromagnetic coupling state, strong spin-orbit coupling appears near the Fermi level and shows no obvious asymmetry for up and down spins, which indicates a significant hybrid effects from Co 3d and O 2p states. The magnetic moments are mainly contributed by unpaired electrons in Co 3d and neighbor O 2p orbital and are correlated to the doped site of Co atoms. In addition, the calculated results of optical properties show that Co doped zinc blende ZnO has a strong absorptive capacity at the visible light, and the absorption peaks have red shift in the high energy region. The theoretical calculated results demonstrate that Co-doped zinc blende ZnO may become excellent magneto-optic materials.