中国物理B ›› 2015, Vol. 24 ›› Issue (3): 34501-034501.doi: 10.1088/1674-1056/24/3/034501

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

High coercivity in large exchange-bias Co/CoO-MgO nano-granular films

葛传楠a b, 万贤纲a, Eric Pellegrinc, 胡志伟d, Wen-I Liange, Michael Brunsf, 邹文琴a, 都有为a   

  1. a National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, China;
    b Department of Physics, Jiangsu Second Normal University, Nanjing 210013, China;
    c CELLS-ALBA Synchrotron Radiation Facility, Carretera BP 1413, km 3.3, Cerdanyola del Vallès (Barcelona) E-08290, Spain;
    d Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, Dresden D-01187, Germany;
    e Lawrence Berkeley National Lab Materials Science Division, Haimei Zheng laboratory, Berkeley CA 94720, USA;
    f Institute for Applied Materials (IAM), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen D-76344, Germany
  • 收稿日期:2014-09-25 修回日期:2014-10-27 出版日期:2015-03-05 发布日期:2015-03-05
  • 基金资助:

    Project supported by the National Basic Research Program of China (Grant No. 2012CB932304), the National Natural Science Foundation of China (Grant Nos. U1232210, 91122035, 11174124, and 11374137), the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (Grant No. 14KJB140003), and the Priority Academic Program Development of Jiangsu Higher Education Institutions, China.

High coercivity in large exchange-bias Co/CoO-MgO nano-granular films

Ge Chuan-Nan (葛传楠)a b, Wan Xian-Gang (万贤纲)a, Eric Pellegrinc, Hu Zhi-Wei (胡志伟)d, Wen-I Liange, Michael Brunsf, Zou Wen-Qin (邹文琴)a, Du You-Wei (都有为)a   

  1. a National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093, China;
    b Department of Physics, Jiangsu Second Normal University, Nanjing 210013, China;
    c CELLS-ALBA Synchrotron Radiation Facility, Carretera BP 1413, km 3.3, Cerdanyola del Vallès (Barcelona) E-08290, Spain;
    d Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, Dresden D-01187, Germany;
    e Lawrence Berkeley National Lab Materials Science Division, Haimei Zheng laboratory, Berkeley CA 94720, USA;
    f Institute for Applied Materials (IAM), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, Eggenstein-Leopoldshafen D-76344, Germany
  • Received:2014-09-25 Revised:2014-10-27 Online:2015-03-05 Published:2015-03-05
  • Contact: Wan Xian-Gang E-mail:xgwan@nju.edu.cn
  • Supported by:

    Project supported by the National Basic Research Program of China (Grant No. 2012CB932304), the National Natural Science Foundation of China (Grant Nos. U1232210, 91122035, 11174124, and 11374137), the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (Grant No. 14KJB140003), and the Priority Academic Program Development of Jiangsu Higher Education Institutions, China.

摘要:

We present a detailed study on the magnetic coercivity of Co/CoO-MgO core-shell systems, which exhibits a large exchange bias due to an increase of the uncompensated spin density at the interface between the CoO shell and the metallic Co core by replacing Co by Mg within the CoO shell. We find a large magnetic coercivity of 7120 Oe around the electrical percolation threshold of the Co/CoO core/shell particles, while samples with a smaller or larger Co metal volume fraction show a considerably smaller coercivity. Thus, this study may lead to a route to improving the magnetic properties of artificial magnetic material in view of potential applications.

关键词: granular films, exchange bias, coercivity

Abstract:

We present a detailed study on the magnetic coercivity of Co/CoO-MgO core-shell systems, which exhibits a large exchange bias due to an increase of the uncompensated spin density at the interface between the CoO shell and the metallic Co core by replacing Co by Mg within the CoO shell. We find a large magnetic coercivity of 7120 Oe around the electrical percolation threshold of the Co/CoO core/shell particles, while samples with a smaller or larger Co metal volume fraction show a considerably smaller coercivity. Thus, this study may lead to a route to improving the magnetic properties of artificial magnetic material in view of potential applications.

Key words: granular films, exchange bias, coercivity

中图分类号:  (Static sandpiles; granular compaction)

  • 45.70.Cc
75.30.Et (Exchange and superexchange interactions) 75.50.Vv (High coercivity materials) 75.60.Ej (Magnetization curves, hysteresis, Barkhausen and related effects)