[10p-N303-1~9] 10.4 Spintronics in semiconductor, topological material, superconductor, and multiferroics

1:45 PM - 2:00 PM JST(4:45 AM - 5:00 AM UTC)

[10p-N303-2] Experiment and Theory of Interfacial Multiferroics Driven by Super-Orbital Splitting at Room Temperature

〇Hiroshi Naganuma¹, Kenji Nawa², Tomohiro Ichinose², Kenta Amemiya³, Takahisa Shiraishi⁴, Yukio Sato⁴, Tetsuya Fukushima² (1.Nagoya Univ.NUIAS, 2.AIST, 3.KEK, 4.Kumamoto Univ.)

Keywords:

Multiferroics,Interface,CIR

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.