Chen Bo, Zhou Baozeng, Wang Xiaocha
Tianjin Key Laboratory of Film Electronic & Communicate Devices, School of Integrated Circuit Science and Engineering, Tianjin University of Technology, Tianjin 300384, China.
Nanoscale. 2024 Jun 27;16(25):12196-12206. doi: 10.1039/d4nr01253d.
Two-dimensional (2D) Janus trihalides have attracted widespread attention due to their potential applications in spintronics. In this work, the valley polarization of MoSe at the K' and K points can be modulated by NiClI, a new 2D Janus trihalide. The NiClI/MoSe heterostructure has an in-plane magnetic anisotropy energy (IMA) and is characterized by three distinct electronic structures: metallic, semiconducting, and half-metallic. It is noted that the semiconducting state features a band gap of 0.07 eV. When spin-orbit coupling (SOC) is considered, valley polarization is exhibited in the NiClI/MoSe heterostructure, with the degree of valley polarization varying across different configurations and reaching a maximum value of 4.6 meV. The electronic properties, valley polarization and MAE of the system can be tuned by biaxial strains. The application of a biaxial strain ranging from -6% to +6% can enhance the valley polarization value from 0.9 meV to 12.9 meV. The directions of MAE of the NiClI/MoSe heterostructure can be changed at biaxial strains of -6%, +2%, +4% and +6%. The above calculation results show that the heterostructure system possesses rich electronic properties and tunability, with extensive potential applications in the fields of spintronic and valleytronic devices.
二维（2D）Janus三卤化物因其在自旋电子学中的潜在应用而受到广泛关注。在这项工作中，新型二维Janus三卤化物NiClI可以调制MoSe在K'和K点处的能谷极化。NiClI/MoSe异质结构具有面内磁各向异性能量（IMA），并具有三种不同的电子结构特征：金属性、半导体性和半金属性。值得注意的是，半导体态的带隙为0.07 eV。当考虑自旋轨道耦合（SOC）时，NiClI/MoSe异质结构中会出现能谷极化，能谷极化程度在不同构型中有所变化，最大值为4.6 meV。该系统的电子性质、能谷极化和MAE可通过双轴应变进行调节。施加范围从-6%到+6%的双轴应变可使能谷极化值从0.9 meV提高到12.9 meV。在-6%、+2%、+4%和+6%的双轴应变下，NiClI/MoSe异质结构的MAE方向会发生变化。上述计算结果表明，该异质结构系统具有丰富的电子性质和可调节性，在自旋电子学和能谷电子学器件领域具有广泛的潜在应用。
