キラルイオンゲート技術を世界初実証～分子対称性によるトポロジカル表面磁性の超省電力制御に成功～

2025-10-14 東京大学

キラルイオンゲートによる二次元磁性表面の制御

＜関連情報＞

• https://www.iis.u-tokyo.ac.jp/ja/news/4897/
• https://pubs.acs.org/doi/10.1021/acs.nanolett.5c03884

キラルイオンゲーティングによる二次元強磁性の電場制御 Electric-Field Control of Two-Dimensional Ferromagnetic Properties by Chiral Ionic Gating

Hideki Matsuoka,Amaki Moriyama,Tomohiro Hori,Yoshinori Tokura,Yoshihiro Iwasa,Shu Seki,Masayuki Suda,and Naoya Kanazawa
Nano Letters  Published October 10, 2025
DOI:https://doi.org/10.1021/acs.nanolett.5c03884

Abstract

Chiral molecular systems offer unique pathways to control spin and magnetism beyond conventional symmetry operations. Here, we demonstrate that chiral ionic liquids enable the electric-field modulation of two-dimensional (2D) ferromagnetism in FeSi(111) thin films via electric double-layer transistor gating. FeSi hosts chemically stable, surface-confined ferromagnetism without bulk moments, making the interfacial spins highly responsive to chiral-ion adsorption. Using both achiral and chiral ionic liquids, we systematically compare the electrochemical and electrostatic gating effects. While both gating modes modulate magnetic properties such as anomalous Hall conductivity and coercive field, only chiral ionic gating biases the ratio of up- and downmagnetized domains in a handedness-dependent manner, evidencing chirality-induced symmetry breaking. This work establishes chiral ion gating as a novel strategy for controlling magnetic order and opens new directions for chiral spintronics.