Magneto-ionic effect in CoFeB thin films with in-plane and perpendicular-to-plane magnetic anisotropy
The magneto-ionic effect is a promising method to control the magnetic properties electrically. Charged mobile oxygen ions can easily be driven by an electric field to modify the magnetic anisotropy of a ferromagnetic layer in contact with an ionic conductor in a solid-state device. In this paper, w...
| Main Authors: | , , , , |
|---|---|
| Other Authors: | |
| Format: | Article |
| Published: |
American Institute of Physics (AIP)
2018
|
| Online Access: | http://hdl.handle.net/1721.1/113220 https://orcid.org/0000-0002-6858-8424 https://orcid.org/0000-0002-8719-2652 |
| Summary: | The magneto-ionic effect is a promising method to control the magnetic properties electrically. Charged mobile oxygen ions can easily be driven by an electric field to modify the magnetic anisotropy of a ferromagnetic layer in contact with an ionic conductor in a solid-state device. In this paper, we report on the room temperature magneto-ionic modulation of the magnetic anisotropy of ultrathin CoFeB films in contact with a GdO[subscript x] layer, as probed by polar micro-Magneto Optical Kerr Effect during the application of a voltage across patterned capacitors. Both Pt/CoFeB/GdO[subscript x] films with perpendicular magnetic anisotropy and Ta/CoFeB/GdO[subscript x] films with uniaxial in-plane magnetic anisotropy in the as-grown state exhibit a sizable dependence of the magnetic anisotropy on the voltage (amplitude, polarity, and time) applied across the oxide. In Pt/CoFeB/GdO[subscript x] multilayers, it is possible to reorient the magnetic anisotropy from perpendicular-to-plane to in-plane, with a variation of the magnetic anisotropy energy greater than 0.2 mJ m[subscript -2]. As for Ta/CoFeB/GdO[subscript x] multilayers, magneto-ionic effects still lead to a sizable variation of the in-plane magnetic anisotropy, but the anisotropy axis remains in-plane. |
|---|