论文标题
通过改变层的数量来调整范德华异质结构的波动和波函数：第一原理研究
Tuning valleys and wave functions of van der Waals heterostructures by varying the number of layers: A first-principles study
论文作者
论文摘要
在Van der waals中，二维过渡金属二核苷（2D TMDC）和孔状态的异质结构在空间上定位在形成长寿命层间层面激子的不同层中。在这里，我们从第一原理研究了其他电子或孔层对MOS2/WSE2 Heterobilayer（HBL）的电子性质的影响，该物质是直接带隙材料。附加层修改了层间杂交，主要影响Q谷上G和电子状态的孔状态的准粒子能量和真实空间延伸。对于足够数量的额外层，频带边缘分别从k移到q或g。将电子层添加到HBL中会导致更高的Q状态，而G状态也不会超出HBL，即使添加了更多的孔层。这些结果提出了一种简单而强大的调整频带边缘的方法，以及TMDC异质结构中电子和孔波函数的真实空间扩展，从而强烈影响层中层激子的寿命和动力学。
In van der Waals heterostructures of two-dimensional transition-metal dichalcogenides (2D TMDCs) electron and hole states are spatially localized in different layers forming long-lived interlayer excitons. Here, we have investigated, from first principles, the influence of additional electron or hole layers on the electronic properties of a MoS2/WSe2 heterobilayer (HBL), which is a direct band gap material. Additional layers modify the interlayer hybridization, mostly affecting the quasiparticle energy and real-space extend of hole states at the G and electron states at the Q valleys. For a sufficient number of additional layers, the band edges move from K to Q or G, respectively. Adding electron layers to the HBL leads to more delocalized Q states, while G states do not extend much beyond the HBL, even when more hole layers are added. These results suggest a simple and yet powerful way to tune band edges and the real-space extend of the electron and hole wave function in TMDC heterostructures, strongly affecting the lifetime and dynamics of interlayer excitons.
