Broad magnetic anisotropy regulation in as-deposited Pt/Co/MgO multilayers by tuning electronic coordination

Abstract

The regulation in the magnetic anisotropy of magnetic films is crucial for developing the magnetic storage and logic devices. The traditional work achieved an effective tunability of the magnetic anisotropy by a subsequent processing of the as-deposited film, such as a post-annealing treatment or electric field application. Here, we proposed an effective method to achieve a direct and broad tunability of the magnetic anisotropy in the as-prepared film by adjusting electronic coordination. Nitrogen (N) atoms were doped in the Co layer of Pt/Co/MgO multilayers to effectively control the electronic coordination of Co and enhance the 3dz2–r2 orbital occupancy of Co for modulating the Co–O orbital hybridization. Consequently, the magnetic anisotropy of the as-deposited film changed from in-plane to perpendicular direction with the N doping, resulting in a significant increment in the magnetic anisotropy energy by 2.48 × 106 erg/cm3. Furthermore, the critical Co thickness with maintaining the perpendicular magnetic anisotropy was enlarged from 1 to 3 nm, which is beneficial for enhancing the stability of nanodevices. These findings provide an effective strategy to tune the magnetic anisotropy of magnetic films toward the applications of various magnetic storage and logic devices.