物理化学学报 >> 2011, Vol. 27 >> Issue (10): 2326-2332.doi: 10.3866/PKU.WHXB20111016

理论与计算化学 上一篇    下一篇

Ni 掺杂ZnO纳米线的电子结构与磁性

张富春1, 张威虎1, 董军堂1, 张志勇2   

  1. 1. 延安大学物理与电子信息学院, 陕西延安 716000;
    2. 西北大学信息科学与技术学院, 西安 710127
  • 收稿日期:2011-05-30 修回日期:2011-07-26 发布日期:2011-09-27
  • 通讯作者: 张富春 E-mail:zhangfuchun72@163.com
  • 基金资助:

    国家自然科学基金(60976069), 陕西省自然科学基金(2010JM8020), 陕西省教育厅专项科研基金(2010JK923, 11JK0846)和延安大学博士科研启动基金(YD2009-01)资助项目

Electronic Structure and Magnetism of Ni-Doped ZnO Nanowires

ZHANG Fu-Chun1, ZHANG Wei-Hu1, DONG Jun-Tang1, ZHANG Zhi-Yong2   

  1. 1. College of Physics & Electronic Information, Yan'an University, Yan'an 716000, Shannxi Province, P. R. China;
    2. School of Information Science and Technology, Northwest University, Xi'an 710127, P. R. China
  • Received:2011-05-30 Revised:2011-07-26 Published:2011-09-27
  • Contact: ZHANG Fu-Chun E-mail:zhangfuchun72@163.com
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (60976069), Natural Science Foundation of Shaanxi Province, China (2010JM8020), Specialized Research Fund of the Educational Committee of Shaanxi Province, China (2010JK923, 11JK0846), and Scientific Research Foundation for Doctor of Yan'an University, China (YD2009-01).

摘要: 采用自旋极化密度泛函理论系统研究了Ni 掺杂ZnO纳米线的电子结构、磁学和光学性质. 磁学性质计算结果显示六种Ni 掺杂ZnO纳米线的磁性耦合体系出现了铁磁(FM)、反铁磁(AFM)和顺磁(PM)三种不同的耦合状态. 能量计算结果表明Ni 原子在纳米线外表面沿[0001]方向替代Zn原子时能量最低, 体系的AFM耦合相对稳定, AFM体系表现出金属性. 态密度计算结果显示FM耦合在费米能级附近出现了明显的自旋极化现象,发生了强烈的Ni 3d 和O 2p 杂化效应, 掺杂产生的磁矩主要来源于Ni 3d 未成对轨道电子和部分O 2p 轨道电子的贡献, FM耦合表现出半金属性. 另外, 光学性质计算结果显示Ni 掺杂ZnO纳米线的远紫外吸收峰发生了红移现象, 而380 nm附近的近紫外吸收峰发生了明显的蓝移现象, 在整个紫外区都表现出了优异的发光性能.以上结果表明Ni 掺杂ZnO纳米线是一种很有前途的磁光电子材料.

关键词: 氧化锌, 纳米线, 第一性原理, 掺杂, 磁学性质

Abstract: Based on spin-polarized density functional theory we studied the electronic structures, magnetic and optical properties of Ni-doped ZnO nanowires. The magnetic results show that three magnetic coupling states are present: ferromagnetic (FM), antiferromagnetic (AFM), and paramagnetic (PM) states for the six kinds of Ni-doped configurations. The calculated energy results indicate that antiferromagnetic coupling is more stable when Ni atoms substitute for Zn atoms in the ZnO nanowires on the outside surface along the [0001] direction. AFM coupling has a metallic nature. The FM results from the density of states show that the spin polarization phenomenon appears near the Fermi level and causes strong hybridization between Ni 3d and O 2p. Moreover, the magnetic moments mainly originate from the unpaired electrons of the Ni 3d orbitals and the electrons of the O 2p orbitals contribute a little to the magnetic moments. The coupling of FM has a half-metal nature. In addition, the optical properties indicate that the absorption peaks show a significant red shift and good emission in the far UV band while a blue shift is apparent for the near UV band (380 nm). These results indicate that the Ni-doped ZnO nanowires are promising magneto-optical electronic materials and they can be used for nanoscale spintronics device materials.

Key words: ZnO, Nanowire, First-principles, Doping, Magnetic property

MSC2000: 

  • O646