講演情報
[10p-N303-2]室温動作する超軌道分裂型の界面マルチフェロイックの実験と理論
〇永沼 博1、名和 憲嗣2、一ノ瀬 智浩2、雨宮 健太3、白石 貴久4、佐藤 幸生4、福島 徹夜2 (1.名古屋大 NUIAS、2.産総研、3.高エネ研、4.熊本大)
キーワード：
マルチフェロイックス、界面、巨大界面応答
Magnetoelectric (ME) coupling in multiferroics is essential for ultra-low-power memory and sensing devices, but conventional materials show weak ME responses at room temperature. Here, we report a novel interfacial multiferroic system exhibiting colossal ME effects at room temperature, formed at the interface between ferroelectric BiFeO3 and metallic Co. Structural and XMCD analyses reveal an around 1 nm interfacial layer with a strong, electrically switchable magnetic moment driven by ferroelectric polarization. First-principles calculations using FUGAKU attribute this behavior to electronic reconstruction due to oxygen vacancies and partial Co substitution. Despite these changes, the interface remains insulating, linked to a unique super-orbital-splitting state. These findings underscore the potential of interface engineering for creating room-temperature, tunable ME devices.