Chen Li, Jiang Chuan, Yang Maoyou, Hu Tao, Meng Yan, Lei Jie, Zhang Mingjian
School of Electronic and Information Engineering (Department of Physics), Qilu University of Technology, Jinan 250353, China.
Department of Data Acquisition, National Instruments, Shanghai 201204, China.
Phys Chem Chem Phys. 2021 Feb 25;23(7):4255-4261. doi: 10.1039/d0cp05531j.
From first-principles calculations, the magnetism and electronic structures of bilayer bismuth (stannum) films at the monolayer CrI3 (CrBr3) interface are studied. The Curie temperature (TC) of CrX3 (X = Br, I) can be enhanced by coupling bilayer bismuth (Bi) with van der Waals (vdW) heterostructures. The n-doping of CrX3, induced by interlayer charge-transfer from the Bi film, leads to the enhancement of TC. The quantum spin Hall phases of bilayer bismuth and stannum films are destroyed by the magnetic substrate. Although the interface system of the bilayer stannum (Sn) film on a CrBr3 monolayer shows a band gap (57 meV), the inexistence of edge states with valence and conduction bands connected across the insulating gap is a manifestation of the trivial state without the feature of quantized anomalous Hall effect in the interface. The percentage reduction of the corresponding work function is 22.6%, 12.7%, 25.4% and 16.5% for Bi/CrI3, Sn/CrI3, Bi/CrBr3 and Sn/CrBr3 interface systems, respectively. Our findings demonstrate that the Bi(Sn)-CrI3(CrBr3) interface system with vdW engineering is an efficient way to tune magnetism and electronic structures, which is of importance for future applications in spintronics and nanoelectronics devices.
通过第一性原理计算，研究了双层铋（锡）薄膜在单层CrI3（CrBr3）界面处的磁性和电子结构。通过将双层铋（Bi）与范德华（vdW）异质结构耦合，可以提高CrX3（X = Br，I）的居里温度（TC）。Bi薄膜的层间电荷转移引起的CrX3的n型掺杂导致TC的提高。双层铋和锡薄膜的量子自旋霍尔相被磁性衬底破坏。尽管CrBr3单层上的双层锡（Sn）薄膜的界面系统显示出带隙（57 meV），但价带和导带的边缘态在绝缘间隙上没有连接，这表明该界面处于平凡态，没有量子反常霍尔效应的特征。对于Bi/CrI3、Sn/CrI3、Bi/CrBr3和Sn/CrBr3界面系统，相应功函数的降低百分比分别为22.6%、12.7%、25.4%和16.5%。我们的研究结果表明，具有vdW工程的Bi（Sn）-CrI3（CrBr3）界面系统是调节磁性和电子结构的有效方法，这对未来在自旋电子学和纳米电子器件中的应用具有重要意义。
