标题： 重建的MoSe$_2$/WSe$_2$异质结构中层间激子的横向扩展态 显示英文标题

标题： Laterally Extended States of Interlayer Excitons in Reconstructed MoSe$_2$/WSe$_2$ Heterostructures

摘要： 由二维过渡金属二硫属化物制成的异质结构被称为探索激子现象的理想平台，从相关莫尔激子到简并的层间激子集合。到目前为止，人们认为某些异质结构中出现的原子重构导致了激子态的主要局域化。我们证明，在重构的MoSe$_2$/WSe$_2$异质结构中的激子态可以远远超出所研究异质结构的莫尔周期性。这些结果基于实空间计算，提供了应变松弛异质结构中层间激子的横向势能图和相应的实空间激子波函数。我们将理论结果与低温光致发光实验相结合，这些实验支持了层间激子的计算能级结构和弛豫特性。 显示英文摘要

摘要： Heterostructures made from 2D transition-metal dichalcogenides are known as ideal platforms to explore excitonic phenomena ranging from correlated moir\'e excitons to degenerate interlayer exciton ensembles. So far, it is assumed that the atomic reconstruction appearing in some of the heterostructures gives rise to a dominating localization of the exciton states. We demonstrate that excitonic states in reconstructed MoSe$_2$/WSe$_2$ heterostructures can extend well beyond the moir\'e periodicity of the investigated heterostructures. The results are based on real-space calculations yielding a lateral potential map for interlayer excitons within the strain-relaxed heterostructures and corresponding real-space excitonic wavefunctions. We combine the theoretical results with cryogenic photoluminescence experiments, which support the computed level structure and relaxation characteristics of the interlayer excitons.