当前位置: X-MOL 学术Physica E Low Dimens. Syst. Nanostruct. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Type II GaS/AlN van der Waals heterostructure: Vertical strain, in-plane biaxial strain and electric field effect
Physica E: Low-dimensional Systems and Nanostructures ( IF 3.3 ) Pub Date : 2020-10-09 , DOI: 10.1016/j.physe.2020.114481
Hui Zou , Mengqi Peng , Wenzhe Zhou , Jiangling Pan , Fangping Ouyang

In this work, the geometrical structure, stability, electronic and optical properties of the GaS/AlN van der Waals heterostructure have been explored based on first principles calculations considering the effect of vertical strain, in-plane biaxial strain and the electric field. It is demonstrated that, the GaS/AlN van der Waals heterostructure possesses an intrinsic typical type-II band alignment with an indirect band gap of 1.65 eV. Due to the difference of work functions between monolayer GaS and AlN, the electrons transfer from AlN layer to GaS layer, causing a build-in electric field which facilitates the separation of free electrons and holes. The band gap value of the heterostructure is insensitive to the vertical strain, while in-plain biaxial strain is an effective way to tune the band gap. The band gap value is in the range of 0.68–1.82 eV under in-plane biaxial strain of −5%–5%. The band offsets of the heterostructure can be increased by positive electric field and decreased by negative electric field. Meanwhile, the type-II band alignment of the heterostructure is retained under vertical strain, in-plane biaxial strain and the electric field. In addition, for the heterostructure, compare to constituent layers, the optical absorption is enhanced in visible region. These results render GaS/AlN heterostructure as a good candidate for photovoltaic devices.



中文翻译:

II型GaS / AlN范德华力异质结构:垂直应变,面内双轴应变和电场效应

在这项工作中,GaS / AlN van der Waals异质结构的几何结构,稳定性,电学和光学性质已经基于考虑垂直应变,面内双轴应变和电场影响的第一性原理计算得到了探索。结果表明,GaS / AlN范德华异质结构具有固有的典型II型能带排列,间接带隙为1.65 eV。由于单层GaS和AlN之间的功函数不同,电子从AlN层转移到GaS层,从而产生了内置电场,有利于自由电子和空穴的分离。异质结构的带隙值对垂直应变不敏感,而平面内双轴应变是调整带隙的有效方法。带隙值在0.68–1的范围内。在-5%–5%的面内双轴应变下为82 eV。异质结构的带隙可以通过正电场增加,而可以通过负电场减少。同时,异质结构的II型能带取向在垂直应变,面内双轴应变和电场下得以保持。另外,对于异质结构,与组成层相比,在可见光区域的光吸收增强。这些结果使得GaS / AlN异质结构成为光伏器件的良好候选者。对于异质结构,与组成层相比,在可见光区域的光吸收增强。这些结果使得GaS / AlN异质结构成为光伏器件的良好候选者。对于异质结构,与组成层相比,在可见光区域的光吸收增强。这些结果使得GaS / AlN异质结构成为光伏器件的良好候选者。

更新日期:2020-10-29
down
wechat
bug