中国物理B ›› 2015, Vol. 24 ›› Issue (11): 117201-117201.doi: 10.1088/1674-1056/24/11/117201

• CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES • 上一篇    下一篇

Tunneling magnetoresistance based on a Cr/graphene/Cr magnetotunnel junction

栾桂苹a, 张沛然a, 焦娜a, 孙立忠b   

  1. a Department of Physics, Xiangtan University, Xiangtan 411105, China;
    b Hunan Provincial Key Laboratory of Thin Film Materials and Devices, School of Materials Scienceand Engineering, Xiangtan University, Xiangtan 411105, China
  • 收稿日期:2015-01-16 修回日期:2015-04-27 出版日期:2015-11-05 发布日期:2015-11-05
  • 通讯作者: Sun Li-Zhong E-mail:lzsun@xtu.edu.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 10874143, 10974166, and 11574260), the Program for New Century Excellent Talents in University, China (Grant No. NCET-10-0169), the National Innovation Foundation for Graduate, China (Grant No. 201310530003), and the Computational Support from Shanghai Super-computer Center, China.

Tunneling magnetoresistance based on a Cr/graphene/Cr magnetotunnel junction

Luan Gui-Ping (栾桂苹)a, Zhang Pei-Ran (张沛然)a, Jiao Na (焦娜)a, Sun Li-Zhong (孙立忠)b   

  1. a Department of Physics, Xiangtan University, Xiangtan 411105, China;
    b Hunan Provincial Key Laboratory of Thin Film Materials and Devices, School of Materials Scienceand Engineering, Xiangtan University, Xiangtan 411105, China
  • Received:2015-01-16 Revised:2015-04-27 Online:2015-11-05 Published:2015-11-05
  • Contact: Sun Li-Zhong E-mail:lzsun@xtu.edu.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 10874143, 10974166, and 11574260), the Program for New Century Excellent Talents in University, China (Grant No. NCET-10-0169), the National Innovation Foundation for Graduate, China (Grant No. 201310530003), and the Computational Support from Shanghai Super-computer Center, China.

摘要: Using the density functional theory and the nonequilibrium Green’s function method, we studied the finite-bias quantum transport in a Cr/graphene/Cr magnetotunnel junction (MTJ) constructed by a single graphene layer sandwiched between two semi-infinite Cr(111) electrodes. We found that the tunneling magnetoresistance (TMR) ratio in this MTJ reached 108%, which is close to that of a perfect spin filter. Under an external positive bias, we found that the TMR ratio remained constant at 65%, in contrast to MgO-based MTJs, the TMR ratios of which decrease with increasing bias. These results indicate that the Cr/graphene/Cr MTJ is a promising candidate for spintronics applications.

关键词: graphene, first-principles method, magnetotunnel junction, tunneling magnetoresistance

Abstract: Using the density functional theory and the nonequilibrium Green’s function method, we studied the finite-bias quantum transport in a Cr/graphene/Cr magnetotunnel junction (MTJ) constructed by a single graphene layer sandwiched between two semi-infinite Cr(111) electrodes. We found that the tunneling magnetoresistance (TMR) ratio in this MTJ reached 108%, which is close to that of a perfect spin filter. Under an external positive bias, we found that the TMR ratio remained constant at 65%, in contrast to MgO-based MTJs, the TMR ratios of which decrease with increasing bias. These results indicate that the Cr/graphene/Cr MTJ is a promising candidate for spintronics applications.

Key words: graphene, first-principles method, magnetotunnel junction, tunneling magnetoresistance

中图分类号:  (Galvanomagnetic and other magnetotransport effects)

  • 72.15.Gd
72.25.Mk (Spin transport through interfaces)