Van der Waals heterostructures obtained via stacking and twisting have been used to create moiré superlattices¹, enabling new optical and electronic properties in solid-state systems. Moiré lattices in twisted bilayers of transition metal dichalcogenides (TMDs) result in exciton trapping^2,3,4,5, host Mott insulating and superconducting states⁶ and act as unique Hubbard systems^7,8,9 whose correlated electronic states can be detected and manipulated optically. Structurally, these twisted heterostructures feature atomic reconstruction and domain formation^{10,11,12,13,14}. However, due to the nanoscale size of moiré domains, the effects of atomic reconstruction on the electronic and excitonic properties have not been systematically investigated. Here we use near-0°-twist-angle MoSe₂/MoSe₂ bilayers with large rhombohedral AB/BA domains¹⁵ to directly probe the excitonic properties of individual domains with far-field optics. We show that this system features broken mirror/inversion symmetry, with the AB and BA domains supporting interlayer excitons with out-of-plane electric dipole moments in opposite directions. The dipole orientation of ground-state Γ–K interlayer excitons can be flipped with electric fields, while higher-energy K–K interlayer excitons undergo field-asymmetric hybridization with intralayer K–K excitons. Our study reveals the impact of crystal symmetry on TMD excitons and points to new avenues for realizing topologically non-trivial systems^16,17, exotic metasurfaces¹⁸, collective excitonic phases¹⁹ and quantum emitter arrays^20,21 via domain-pattern engineering.

通过堆叠和扭曲获得的范德华异质结构已被用于创建莫尔超晶格¹，从而在固态系统中实现了新的光学和电子性能。过渡金属二硫化氢（TMDs）的扭曲双层中的莫尔晶格导致激子俘获^2,3,4,5，具有Mott绝缘和超导态^6，并充当独特的Hubbard系统^7,8,9，其相关电子态可以被检测到并光学操作。这些扭曲的异质结构在结构上具有原子重构和畴形成的特征^{10,11,12,13,14}。然而，由于莫尔域的纳米级尺寸，原子重构对电子和激子性质的影响尚未得到系统的研究。在这里，我们使用具有大菱形AB / BA域的接近0°扭转角的MoSe ₂ / MoSe ₂双层¹⁵用远场光学器件直接探测各个域的激子性质。我们表明，该系统具有破碎的镜像/反对称性，AB和BA域支持层间激子，且层间激子具有相反方向的平面电偶极矩。基态Γ-K层间激子的偶极子方向可以被电场翻转，而高能K-K层间激子与层内K-K激子发生场不对称杂交。我们的研究揭示了晶体对称性对TMD激子的影响，并为实现拓扑非平凡系统^16,17，奇异超表面¹⁸，集体激子相¹⁹和量子发射体阵列^20,21提供了新途径。 通过领域模式工程。