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arXiv · 2506.08806

Ferromagnetic Two-dimensional Electron Gases with Magnetic Doping and Proximity Effects

Abstract

The advent of magnetic two-dimensional electron gases (2DEGs) at oxide interfaces has provided new opportunities in the field of spintronics. The enhancement of magnetism in 2DEGs at oxide interfaces continues to be a significant challenge, as exemplified by the relatively weak magnetism observed in the classical LaAlO3/SrTiO3 interface. Here, we present ferromagnetic (FM) 2DEGs at the interface fabricated between the FM insulator EuTiO3 (ETO) and the strong spin-orbit coupled (SOC) perovskite insulator KTaO3 (KTO). With the combined effects of magnetic atom doping and magnetic proximity from ETO films, the coercive field of 2DEGs can be significantly enhanced. Magnetoresistance (MR) curve with a high coercive field of 1000 Oe has been observed, in conjunction with a temperature-dependent unambiguous hysteresis loop in the anomalous Hall effect (AHE). Furthermore, within the 2DEGs, we have identified a synergetic interplay between magnetic scattering and the weak antilocalization (WAL) effect on transport. This study provides fresh insights into the formation of FM 2DEGs at ETO/KTO interfaces, and introduce an innovative pathway for creating high-performance magnetic 2DEGs at oxide interfaces.

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Zixin Fan, Jiale Chen, Qiangtao Sui, Haoming Ling, Zihao Wang, Lingyuan Kong, Dingyi Li, Fang Yang, Run Zhao, Hanghui Chen, Pan Chen, Yan Liang, Jiandi Zhang. 2025-06-10. Ferromagnetic Two-dimensional Electron Gases with Magnetic Doping and Proximity Effects. https://doi.org/10.1103/physrevb.111.235415

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