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arXiv · 2308.08876

Interfacial Fe segregation and its influence on magnetic properties of CoFeB/MgFeO multilayers

Tomohiro Ichinose·Tatsuya Yamamoto·Takayuki Nozaki·Kay Yakushiji·Shingo Tamaru·Shinji Yuasa
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Abstract

We investigated the effect of Fe segregated from partially Fe-substituted MgO (MgFeO) on the magnetic properties of CoFeB/MgFeO multilayers. X-ray photoelectron spectroscopy (XPS) as well as magnetic measurements revealed that the segregated Fe was reduced to metal and exhibited ferromagnetism at the CoFeB/MgFeO interface. The CoFeB/MgFeO multilayer showed more than 2-fold enhancement in perpendicular magnetic anisotropy (PMA) energy density compared with a standard CoFeB/MgO multilayer. The PMA energy density was further enhanced by inserting an ultrathin MgO layer in between CoFeB and MgFeO layers. Ferromagnetic resonance measurement also revealed a remarkable reduction of magnetic damping in the CoFeB/MgFeO multilayers.

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Tomohiro Ichinose, Tatsuya Yamamoto, Takayuki Nozaki, Kay Yakushiji, Shingo Tamaru, Shinji Yuasa. 2023-08-17. Interfacial Fe segregation and its influence on magnetic properties of CoFeB/MgFeO multilayers. https://arxiv.org/abs/2308.08876

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