Science China Technological Sciences

, Volume 62, Issue 11, pp 2009–2013 | Cite as

Large lattice mismatch induced perpendicular magnetic anisotropy and perpendicular exchange bias in CoPt/FeMn bilayer films

  • ChunJiao Pan
  • TengHua Gao
  • Nobuhide Itogawa
  • Takashi Harumoto
  • ZhengJun Zhang
  • Yoshio Nakamura
  • Ji ShiEmail author


Perpendicular magnetic anisotropy and perpendicular exchange bias of CoPt/FeMn bilayers fabricated by dc magnetron sputtering were investigated in this work. Magnetic anisotropy, showing strong dependence on thickness of CoPt layer, changes from perpendicular magnetic anisotropy (PMA) into in-plane magnetic anisotropy when CoPt layer is thicker than 4.5 nm. The evolution of internal stress with thickness, from tensile to compressive, has been analyzed by sin2ψ method using an equal biaxial stress model. Distinctive perpendicular exchange bias (PEB) has been successfully established due to PMA of CoPt and out-of-plane spin component of 3Q-spin-structured FeMn. FeMn thickness dependence of exchange bias field has been systematically investigated.


perpendicular magnetic anisotropy perpendicular exchange bias X-ray technique magnetic materials 


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© Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • ChunJiao Pan
    • 1
    • 2
  • TengHua Gao
    • 2
    • 3
  • Nobuhide Itogawa
    • 2
  • Takashi Harumoto
    • 2
  • ZhengJun Zhang
    • 1
  • Yoshio Nakamura
    • 2
  • Ji Shi
    • 2
    Email author
  1. 1.School of Materials Science and EngineeringTsinghua UniversityBeijingChina
  2. 2.School of Materials and Chemical TechnologyTokyo Institute of TechnologyTokyoJapan
  3. 3.Department of Applied Physics and Physico-InformaticsKeio UniversityTokyoJapan

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