強誘電体の自発分極による強磁性体の保磁力の変化を確認～次世代低消費電力磁気メモリの構築へ前進～

2025-05-09 東京科学大学

図2. 強誘電体を積層して強磁性体の磁気異方性制御を狙ったイメージ図

＜関連情報＞

• https://www.isct.ac.jp/ja/news/xdxp76rmzafv
• https://www.isct.ac.jp/plugins/cms/component_download_file.php?type=2&pageId=&contentsId=1&contentsDataId=1520&prevId=&key=459bf130a1ae2fa809ad4149e9edea36.pdf
• https://iopscience.iop.org/article/10.35848/1882-0786/adbf65

強誘電分極によるCoFeB薄層の磁性制御 Magnetism control of thin CoFeB layers by ferroelectric polarization

Yan Wu, Kazushi Onimura, Hiroyuki Kobayashi, Satoshi Okamoto and Kuniyuki Kakushima
Applied Physics Express  Published: 26 March 2025
DOI:10.35848/1882-0786/adbf65

Abstract

Nonvolatile and reversible control of perpendicular magnetic properties of thin Co_0.2Fe_0.6B_0.2 layers formed on a MgO layer was demonstrated by ferroelectric switching of the stacked Al_0.88Sc_0.12N and Ta₂O₅ layers. A change in the coercivity (H_c) of the 1.3-nm-thick Co_0.2Fe_0.6B_0.2 layer from 30 to 141 Oe was confirmed by depleting electrons at the interface, modifying the magnetic domain wall energy. Saturation magnetization showed a slight decrease toward depletion condition, presumably presenting a dead layer at the interface. The ferroelectric polarization-induced control of magnetism has high potential for magnetic memory applications.