Li Hao, Yang Yali, Deng Shiqing, Liu Hui, Li Tianyu, Song Yuzhu, Bai He, Zhu Tao, Wang Jiaou, Wang Huanhua, Guo Er-Jia, Xing Xianran, Xiang Hongjun, Chen Jun
Beijing Advanced Innovation Center for Materials Genome Engineering and Department of Physical Chemistry, University of Science and Technology Beijing, Beijing100083, China.
Key Laboratory of Computational Physical Sciences (Ministry of Education), State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai200433, China.
Nano Lett. 2023 Feb 22;23(4):1273-1279. doi: 10.1021/acs.nanolett.2c04447. Epub 2023 Feb 2.
Regulating the magnetic properties of multiferroics lays the foundation for their prospective application in spintronic devices. Single-phase multiferroics, such as rare-earth ferrites, are promising candidates; however, they typically exhibit weak magnetism at room temperature (RT). Here, we significantly boosted the RT ferromagnetism of a representative ferrite, EuFeO, by oxygen defect engineering. Polarized neutron reflectometry and magnetometry measurements reveal that saturation magnetization reaches 0.04 μ/Fe, which is approximately 5 times higher than its bulk phase. Combining the annular bright-field images with theoretical assessment, we unravel the underlying mechanism for magnetic enhancement, in which the decrease in Fe-O-Fe bond angles caused by oxygen vacancies () strengthens magnetic interactions and tilts Fe spins. Furthermore, the internal relationship between magnetism and was established by illustrating how the magnetic structure and magnitude change with configuration and concentration. Our strategy for regulating magnetic properties can be applied to numerous functional oxide materials.
调控多铁性材料的磁性能为其在自旋电子器件中的潜在应用奠定了基础。单相多铁性材料，如稀土铁氧体，是很有前景的候选材料；然而，它们在室温下通常表现出较弱的磁性。在此，我们通过氧缺陷工程显著提高了一种代表性铁氧体EuFeO的室温铁磁性。极化中子反射测量和磁测量结果表明，饱和磁化强度达到0.04 μ/Fe，约为其体相的5倍。结合环形明场图像和理论评估，我们揭示了磁增强的潜在机制，其中氧空位导致的Fe-O-Fe键角减小增强了磁相互作用并使Fe自旋倾斜。此外，通过说明磁结构和大小如何随氧空位构型和浓度变化，建立了磁性与氧空位之间的内在关系。我们调控磁性能的策略可应用于众多功能氧化物材料。
