中国物理B ›› 2019, Vol. 28 ›› Issue (10): 108503-108503.doi: 10.1088/1674-1056/ab3b50

• INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY • 上一篇    下一篇

Designing of spin filter devices based on zigzag zinc oxide nanoribbon modified by edge defect

Bao-Rui Huang(黄保瑞), Fu-Chun Zhang(张富春), Yan-Ning Yang(杨延宁), Zhi-Yong Zhang(张志勇), Wei-Guo Wang(王卫国)   

  1. 1 School of Information Science Technology, Northwest University, Xi'an 710127, China;
    2 School of Physics and Electronic Information, Yan'an University, Yan'an 716000, China
  • 收稿日期:2019-06-05 修回日期:2019-08-11 出版日期:2019-10-05 发布日期:2019-10-05
  • 通讯作者: Zhi-Yong Zhang E-mail:zhangzy@nwu.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61664008 and 11604286) and the Scientific Technological Innovation Team of Yan'an City, China (Grant No. 2017CXTD-01).

Designing of spin filter devices based on zigzag zinc oxide nanoribbon modified by edge defect

Bao-Rui Huang(黄保瑞)1,2, Fu-Chun Zhang(张富春)2, Yan-Ning Yang(杨延宁)2, Zhi-Yong Zhang(张志勇)1, Wei-Guo Wang(王卫国)2   

  1. 1 School of Information Science Technology, Northwest University, Xi'an 710127, China;
    2 School of Physics and Electronic Information, Yan'an University, Yan'an 716000, China
  • Received:2019-06-05 Revised:2019-08-11 Online:2019-10-05 Published:2019-10-05
  • Contact: Zhi-Yong Zhang E-mail:zhangzy@nwu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61664008 and 11604286) and the Scientific Technological Innovation Team of Yan'an City, China (Grant No. 2017CXTD-01).

摘要: The spin-dependent electronic transport properties of a zigzag zinc oxide (ZnO) nanoribbon are studied by using density functional theory with non-equilibrium Green's functions. We calculate the spin-polarized band structure, projected density of states, Bloch states, and transmission spectrum of the ZnO nanoribbon. It is determined that all Bloch states are located at the edge of the ZnO nanoribbon. The spin-up transmission eigenchannels are contributed from Zn 4s orbital, whereas the spin-down transmission eigenchannels are contributed from Zn 4s and O 2p orbitals. By analyzing the current-voltage curves for the opposite spins of the ZnO nanoribbon device, negative differential resistance (NDR) and spin filter effect are observed. Moreover, by constructing the ZnO nanoribbon modified by the Zn-edge defect, the spin-up current is severely suppressed because of the destruction of the spin-up transmission eigenchannels. However, the spin-down current is preserved, thus resulting in the perfect spin filter effect. Our results indicate that the ZnO nanoribbon modulated by the edge defect is a practical design for a spin filter.

关键词: ZnO nanoribbon, spin-dependent transport, nonequilibrium Green', s functions, transmission eigenchannels, spin filtering efficiency

Abstract: The spin-dependent electronic transport properties of a zigzag zinc oxide (ZnO) nanoribbon are studied by using density functional theory with non-equilibrium Green's functions. We calculate the spin-polarized band structure, projected density of states, Bloch states, and transmission spectrum of the ZnO nanoribbon. It is determined that all Bloch states are located at the edge of the ZnO nanoribbon. The spin-up transmission eigenchannels are contributed from Zn 4s orbital, whereas the spin-down transmission eigenchannels are contributed from Zn 4s and O 2p orbitals. By analyzing the current-voltage curves for the opposite spins of the ZnO nanoribbon device, negative differential resistance (NDR) and spin filter effect are observed. Moreover, by constructing the ZnO nanoribbon modified by the Zn-edge defect, the spin-up current is severely suppressed because of the destruction of the spin-up transmission eigenchannels. However, the spin-down current is preserved, thus resulting in the perfect spin filter effect. Our results indicate that the ZnO nanoribbon modulated by the edge defect is a practical design for a spin filter.

Key words: ZnO nanoribbon, spin-dependent transport, nonequilibrium Green', s functions, transmission eigenchannels, spin filtering efficiency

中图分类号:  (Magnetoelectronics; spintronics: devices exploiting spin polarized transport or integrated magnetic fields)

  • 85.75.-d
73.63.-b (Electronic transport in nanoscale materials and structures)