Current Applied Physics

Korean Physical Society (한국물리학회)
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X-ray scattering study on the electric field-induced interfacial magnetic anisotropy modulation at CoFeB / MgO interfaces

  • Song, Kyung Mee (Center for Spintronics, Korea Institute of Science and Technology) ;
  • Kim, Dong-Ok (Center for Spintronics, Korea Institute of Science and Technology) ;
  • Kim, Jae-Sung (Department of Physics, Sookmyung Women's University) ;
  • Lee, Dong Ryeol (Department of Physics, Soongsil University) ;
  • Choi, Jun Woo (Center for Spintronics, Korea Institute of Science and Technology)
  • Received : 2018.04.14
  • Accepted : 2018.05.03
  • Published : 2018.11.30
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Abstract

The electric field-induced modifications of magnetic anisotropy in CoFeB/MgO systems are studied using X-ray resonant magnetic scattering and magneto-optical Kerr effect. Voltage dependent changes of the magnetic anisotropy of -12.7 fJ/Vm and -8.32 fJ/Vm are observed for Ta/CoFeB/MgO and Hf/CoFeB/MgO systems, respectively. This implies that the interfacial perpendicular magnetic anisotropy is reduced (enhanced) when electron density is increased (decreased). X-ray resonant magnetic scattering measurements reveal that the small in-plane magnetic component of the remanent state of CoFeB/MgO systems with weak magnetic anisotropy changes depending on the applied voltage leading to modification of the magnetic anisotropy at the CoFeB/MgO interface.

Keywords

Acknowledgement

Supported by : National Research Council of Science and Technology, KIST

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