Long lifetimes of spatially indirect excitons (IXs), also known as interlayer excitons, allow implementing both quantum exciton systems and long-range exciton transport. The van der Waals heterostructures composed of atomically thin layers of transition-metal dichalcogenides offer the opportunity to explore IXs in moiré superlattices. IX transport in transition-metal dichalcogenide heterostructures was intensively studied and diffusive IX transport with 1/e decay distances up to ~4 μm was realized. Here, in a MoSe₂/WSe₂ heterostructure, we present the IX long-range transport with 1/e decay distances reaching and exceeding 100 μm. The IX long-range transport vanishes at temperatures above ~10 K. With increasing IX density, IX localization followed by IX long-range transport and IX re-entrant localization are observed. The non-monotonic dependence of IX transport on density is in qualitative agreement with the Bose–Hubbard theory prediction for superfluid and insulating phases in periodic potentials of moiré superlattices.

空间间接激子（IX）（也称为层间激子）的长寿命允许实现量子激子系统和长程激子传输。由原子级薄层过渡金属二硫族化物组成的范德华异质结构为探索莫尔超晶格中的 IX 提供了机会。对过渡金属二硫属化物异质结构中的 IX 输运进行了深入研究，并实现了 1/ e衰减距离高达约 4 μm 的扩散 IX 输运。在这里，在 MoSe ₂ /WSe ₂异质结构中，我们提出了 IX 长程传输，其 1/ e衰减距离达到并超过 100 μm。 IX 长程传输在温度高于 ~10 K 时消失。随着 IX 密度的增加，观察到 IX 定位，然后是 IX 长程传输和 IX 重入定位。 IX 输运对密度的非单调依赖性与玻色-哈伯德理论对莫尔超晶格周期性势中的超流体和绝缘相的预测在质量上一致。