Voltage-driven 90 switching of bulk perpendicular magnetic anisotropy in ferrimagnets

Zhengyu Xiao; Ruiwen Xie; Fernando Maccari; Philipp Klaassen; Benedikt Eggert; Di Wang; Yuting Dai; Raquel Lizarraga; Johanna Lill; Tom Helbig; Heiko Wende; Kurt Kummer; Katharina Ollefs; Konstantin Skokov; Hongbin Zhang; Zhiyong Quan; Xiaohong Xu; Robert Kruk; Horst Hahn; Oliver Gutfleisch; Xinglong Ye

arXiv · 2312.00643

Voltage-driven 90 switching of bulk perpendicular magnetic anisotropy in ferrimagnets

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Abstract

Unravelling the mechanism behind bulk perpendicular magnetic anisotropy (PMA) in amorphous rare earth-transition metal films has proven challenging. This is largely due to the inherent complexity of amorphous structure and the entangled potential origins arising from microstructure and atomic structure factors. Here, we present an approach wherein the magneto-electric effect is harnessed to induce 90{\deg} switching of bulk PMA in Tb-Co films to in-plane directions by applying voltages of only -1.2 V. This manipulation is achieved by voltage-driven insertion of hydrogen atoms into interstitial sites between Tb and Co atoms, which serves as a perturbation to local atomic structure. Using angle-dependent X-ray magnetic circular dichroism, we find that the anisotropy switching originates from the distortion of crystal field around Tb which reorients the alignment of Tb orbital moments. Initially aligned along Tb-Co bonding directions, the easy magnetization axis undergoes reorientation and switches by 90{\deg}, as substantiated by ab-initio calculations. Our study not only concludes the atomic origin of Tb-Co atom bonding configuration in shaping bulk PMA, but also establishes the groundwork for electrically programmable ferrimagnetic spintronics, such as controlling domain wall motion and programming artificial spin textures.

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Zhengyu Xiao, Ruiwen Xie, Fernando Maccari, Philipp Klaassen, Benedikt Eggert, Di Wang, Yuting Dai, Raquel Lizarraga, Johanna Lill, Tom Helbig, Heiko Wende, Kurt Kummer, Katharina Ollefs, Konstantin Skokov, Hongbin Zhang, Zhiyong Quan, Xiaohong Xu, Robert Kruk, Horst Hahn, Oliver Gutfleisch, Xinglong Ye. 2023-12-01. Voltage-driven 90 switching of bulk perpendicular magnetic anisotropy in ferrimagnets. https://arxiv.org/abs/2312.00643

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