Xi Yilian, Shi Hanqing, Zhang Jingwei, Li Heping, Cheng Ningyan, Xu Hang, Liu Jiaqi, Li Keren, Guo Huaiming, Feng Haifeng, Wang Jianfeng, Hao Weichang, Du Yi
School of Physics, Beihang University, Haidian District, Beijing 100191, People's Republic of China.
Information Materials and Intelligent Sensing Laboratory of Anhui Province, Leibniz International Joint Research Center of Materials Sciences of Anhui Province, Institute of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, People's Republic of China.
J Phys Chem Lett. 2024 Oct 31;15(43):10802-10810. doi: 10.1021/acs.jpclett.4c02426. Epub 2024 Oct 21.
Discoveries of above-room-temperature intrinsic ferromagnetism in two-dimensional (2D) van der Waals (vdW) materials offer a platform for studying fundamental 2D magnetism and spintronic devices, especially the recently discovered above-room-temperature 2D vdW FeGaTe (FGaT). However, the magnetic mechanism in FGaT remains elusive. Here, a detailed investigation using magnetic force microscopy on the thickness-dependent magnetic behavior of FGaT single crystals is reported. The Heisenberg exchange interaction constant () at room temperature is determined to be 1.32836 × 10 J/m. Our study combining angle-resolved photoemission spectroscopy and density functional theory suggests that the high Curie temperature in FGaT is attributed to the shift of the localized Fe band toward the Fermi level as well as the enhanced magnetic exchange effect due to the strong itinerant ability of Fe. This work sheds light on the understanding of magnetism in FGaT and provides a promising platform to investigate the mechanisms of 2D magnetic materials.
二维（2D）范德华（vdW）材料中本征铁磁性在室温以上的发现为研究基本的二维磁性和自旋电子器件提供了一个平台，特别是最近发现的室温以上二维vdW FeGaTe（FGaT）。然而，FGaT中的磁机制仍然难以捉摸。在此，报道了一项使用磁力显微镜对FGaT单晶厚度依赖性磁行为的详细研究。室温下的海森堡交换相互作用常数（）被确定为1.32836×10 J/m。我们结合角分辨光电子能谱和密度泛函理论的研究表明，FGaT中的高居里温度归因于局域化Fe能带向费米能级的移动以及由于Fe的强巡游能力而增强的磁交换效应。这项工作有助于理解FGaT中的磁性，并为研究二维磁性材料的机制提供了一个有前景的平台。
