Pang KaiJuan, Wei YaDong, Xu Xiaodong, Li WeiQi, Yang JianQun, Zhang GuiLing, Li XingJi, Ying Tao, Jiang YongYuan
School of Physics, Harbin Institute of Technology, Harbin 150001, China.
Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
Phys Chem Chem Phys. 2020 Sep 30;22(37):21412-21420. doi: 10.1039/d0cp03486j.
Using the density functional theory (DFT) calculations, we find that Janus group-III chalcogenide monolayers can serve as a suitable substrate for silicene, and the Dirac electron band properties of silicene are also fully preserved. The maximum opened band gap can reach 179 meV at the Dirac point due to the interaction of silicene and the polar two-dimensional (2D) substrate. In addition, the electronic band structure of the heterostructure can be modulated by applying an electric field where its predicted band gap increases or decreases according to the direction of the applied external electric field. Furthermore, an insight into the electron structures can be understood by analyzing the electron energy-loss (EEL) spectra. From these results, we also predict that heterostructures with polar 2D substrates have broad application prospects in multi-functional devices. Besides, Janus group-III chalcogenide monolayers can be used as good substrates for growing silicene and the modulation of the electronic structure can also be applied to nanodevices and optoelectronic devices.
通过密度泛函理论（DFT）计算，我们发现Janus III族硫族化物单层可以作为硅烯的合适衬底，并且硅烯的狄拉克电子能带性质也能得到充分保留。由于硅烯与极性二维（2D）衬底的相互作用，在狄拉克点处最大打开的带隙可达179毫电子伏特。此外，通过施加电场可以调制异质结构的电子能带结构，其预测的带隙会根据所施加外部电场的方向增大或减小。此外，通过分析电子能量损失（EEL）光谱可以深入了解电子结构。从这些结果中，我们还预测具有极性2D衬底的异质结构在多功能器件中具有广阔的应用前景。此外，Janus III族硫族化物单层可以用作生长硅烯的良好衬底，并且电子结构的调制也可以应用于纳米器件和光电器件。
