Magnetic anisotropy switching of rare earth-transition metal ferrimagnet film by orbital hybridization engineering

Rare earth-transition metal ferrimagnetic films with tunable perpendicular magnetic anisotropy (PMA) play a crucial role in the development of high-performance ferrimagnet-based spintronic devices. Currently, most studies have realized PMA of ferrimagnet based on bulk anisotropy, relying on accurate composition-control or post-intervention. This paper presents a promising strategy for realizing tunable PMA by regulating interfacial anisotropy via orbital hybridization engineering. A Pt/CoGd/MgO heterostructure was designed to introduce the oxygen-ion-associated orbital hybridization to modulate the magnetic exchange interaction within the CoGd alloy, enabling controllable switching between in-plane and out-of-plane magnetic anisotropy. The magnetic anisotropy transformation is strongly influenced by the coordination environment determined by the stacking sequence of multilayers, which derives from the variations of oxygen migration and the related orbital hybridization modification. These findings not only provide a feasible idea for the magnetic anisotropy manipulation in ferrimagnetic films, but also advance the development of efficient ferrimagnet-based spintronic devices.