Li Bo, Wan Zhong, Wang Cong, Chen Peng, Huang Bevin, Cheng Xing, Qian Qi, Li Jia, Zhang Zhengwei, Sun Guangzhuang, Zhao Bei, Ma Huifang, Wu Ruixia, Wei Zhongming, Liu Yuan, Liao Lei, Ye Yu, Huang Yu, Xu Xiaodong, Duan Xidong, Ji Wei, Duan Xiangfeng
Hunan Key Laboratory of Two-Dimensional Materials, Key Laboratory for Micro/Nano-Optoelectronic Devices, Ministry of Education, State Key Laboratory for Chemo/Biosensing and Chemometrics, Department of Applied Physics, School of Physics and Electronics, Hunan University, Changsha, China.
Hunan Key Laboratory of Two-Dimensional Materials and State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, China.
Nat Mater. 2021 Jun;20(6):818-825. doi: 10.1038/s41563-021-00927-2. Epub 2021 Mar 1.
The discovery of intrinsic ferromagnetism in ultrathin two-dimensional van der Waals crystals opens up exciting prospects for exploring magnetism in the ultimate two-dimensional limit. Here, we show that environmentally stable CrSe nanosheets can be readily grown on a dangling-bond-free WSe substrate with systematically tunable thickness down to the monolayer limit. These CrSe/WSe heterostructures display high-quality van der Waals interfaces with well-resolved moiré superlattices and ferromagnetic behaviour. We find no apparent change in surface roughness or magnetic properties after months of exposure in air. Our calculations suggest that charge transfer from the WSe substrate and interlayer coupling within CrSe play a critical role in the magnetic order in few-layer CrSe nanosheets. The highly controllable growth of environmentally stable CrSe nanosheets with tunable thickness defines a robust two-dimensional magnet for fundamental studies and potential applications in magnetoelectronic and spintronic devices.
在超薄二维范德华晶体中发现本征铁磁性，为在极限二维条件下探索磁性开辟了令人兴奋的前景。在此，我们表明，环境稳定的CrSe纳米片可以很容易地生长在无悬键的WSe衬底上，其厚度可系统调节至单层极限。这些CrSe/WSe异质结构表现出高质量的范德华界面，具有清晰分辨的莫尔超晶格和铁磁行为。我们发现，在空气中暴露数月后，表面粗糙度或磁性没有明显变化。我们的计算表明，来自WSe衬底的电荷转移和CrSe层间耦合在少层CrSe纳米片的磁序中起着关键作用。具有可调节厚度的环境稳定CrSe纳米片的高度可控生长，为基础研究以及磁电子和自旋电子器件的潜在应用定义了一种稳健的二维磁体。
