ワイル反強磁性体による交換バイアスの室温制御に成功～新奇な磁気秩序を活かした機能設計が導く、スピントロニクス技術の新展開～

2025-06-17 東京大学

Mn₃Sn/強磁性体2層膜における交換バイアスの等温磁場印加による制御

＜関連情報＞

• https://www.s.u-tokyo.ac.jp/ja/press/10829/
• https://pubs.acs.org/doi/10.1021/acs.nanolett.5c00988

室温における金属FM/AFMヘテロ構造における交換バイアスの磁場スイッチング Magnetic Field Switching of Exchange Bias in a Metallic FM/AFM Heterostructure at Room Temperature

Mihiro Asakura,Tomoya Higo,Takumi Matsuo,Yutaro Tsushima,Shun’ichiro Kurosawa,Ryota Uesugi,Daisuke Nishio-Hamane,and Satoru Nakatsuji
Nano Letters  Published: June 17, 2025
DOI:https://doi.org/10.1021/acs.nanolett.5c00988

Abstract

The exchange bias effect, which causes a shift in the ferromagnetic hysteresis loop due to magnetic coupling with an adjacent antiferromagnetic layer, has been a key area of study for fundamental research and spintronic applications. This effect is known to be static once established through a field cooling procedure and is difficult to manipulate isothermally. Here we present the first room temperature field switching of interlayer magnetic coupling at the metallic heterointerface between a ferromagnet and antiferromaget. Specifically, we demonstrate that the exchange bias can be systematically switched by manipulating the global time-reversal-symmetry-broken antiferromagnetic order of Mn₃Sn via both magnetic field sweeping and field cooling. Furthermore, we confirm that the magnitude and sign of the interlayer coupling can be tuned by selecting the ferromagnet. These findings provide a novel approach for controlling the magnetic state of ferromagnets and functional antiferromagnets, paving the way for advancing spintronic technologies using antiferromagnets.