2025/10/01 by Nozomi Soya, Sakura Yoshikawa, Takayoshi Katase +1 · 1 voice · 1 citation
Materials Science · #Electronic and Structural Properties of Oxides #Magnetic and transport properties of perovskites and related materials #Ferroelectric and Piezoelectric Materials
paper · pdf · doi:10.1038/s44306-025-00102-2
openalex publication_date 2025/10/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/22
Spin-orbit torques (SOTs) offer a promising approach for fast, low-power magnetization manipulation in information technologies. Two-dimensional electron gases (2DEGs) formed at oxide interfaces are known to exhibit high SOT efficiency, attracting significant interest for their potential in the development of efficient SOT devices. Here, contrary to this common expectation, we reveal that the high SOT efficiency observed in SrTiO 3 -based devices—a representative oxide system—is largely superficial. Through spin-torque ferromagnetic resonance (ST-FMR) measurements, we find that the SOT efficiency in the SrTiO 3 -based devices is almost independent of the 2DEG formation and instead scales with the thickness and saturation magnetization of the ferromagnetic layer. This observation demonstrates that the SOT efficiency is primarily governed by current-induced Oersted fields rather than SOTs. These results prompt a revisit of previous experimental findings for a deeper understanding of SOTs in oxide 2DEGs, which is essential for advancing the design of highly efficient spintronic devices.