|Title||Magneto-ionic effect in CoFeB thin films with in-plane and perpendicular-to-plane magnetic anisotropy|
|Publication Type||Journal Article|
|Year of Publication||2017|
|Authors||Baldrati, L, Tan, AJ, Mann, M, Bertacco, R, Beach, GSD|
|Journal||Applied Physics Letters|
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 GdOx layer, as probed by polar micro-Magneto Optical Kerr Effect during the application of a voltage across patterned capacitors. Both Pt/CoFeB/ GdOx films with perpendicular magnetic anisotropy and Ta/CoFeB/GdOx 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/ GdOx 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(-2). As for Ta/CoFeB/GdOx multilayers, magneto-ionic effects still lead to a sizable variation of the in-plane magnetic anisotropy, but the anisotropy axis remains in-plane. Published by AIP Publishing.
|Short Title||Appl. Phys. Lett.|