论文标题
在Moire激子上放下灯光：第一原则的视角
Shedding Light on Moire Excitons: A First-Principles Perspective
论文作者
论文摘要
Van der Waals（VDW）异质结构中的Moire超晶格可能会捕获牢固的粘合和长期存在的层间激子。假定是本地化的，这些摩尔激子可以形成有序的量子点阵列，为新型的光电和量子信息应用铺平了道路。在这里，我们执行第一个原理模拟，以阐明扭曲的MOS2/WS2异质结构中的Moire激子。我们提供了VDW异质结构中局部层间Moire激子的直接证据。基于能量间隙的空间调制，将摩尔电势绘制出来。在没有魔法角度的异质结构中观察到几乎平坦的价波段。研究了Moire激子对异质结构的扭曲角度的空间定位和结合能的依赖性。我们探索如何调整电场以控制Moire激子的位置，极性，发射能和杂交强度。我们预测，交替的电场可以调节杂交Moire激子的偶极矩，并抑制其在Moire Lattices中的扩散。
Moire superlattices in van der Waals (vdW) heterostructures could trap strongly bonded and long lived interlayer excitons. Assumed to be localized, these moire excitons could form ordered quantum dot arrays, paving the way for novel optoelectronic and quantum information applications. Here we perform first principles simulations to shed light on moire excitons in twisted MoS2/WS2 heterostructures. We provide the direct evidence of localized interlayer moire excitons in vdW heterostructures. The moire potentials are mapped out based on spatial modulations of energy gaps. Nearly flat valence bands are observed in the heterostructures without magic angles. The dependence of spatial localization and binding energy of the moire excitons on the twist angle of the heterostructures is examined. We explore how electric field can be tuned to control the position, polarity, emission energy, and hybridization strength of the moire excitons. We predict that alternating electric fields could modulate the dipole moments of hybridized moire excitons and suppress their diffusion in Moire lattices.
