标题： 间接激子在范德华异质结构中的高效传输 显示英文标题

标题： Efficient transport of indirect excitons in a van der Waals heterostructure

摘要： 激子输运对于理解玻色系统中的输运现象以及材料中的激发能传递至关重要。 空间间接激子（IXs）由分层的电子和空穴组成。 长寿命的IX允许它们形成量子玻色态并传播长距离。 在本工作中，我们通过时间分辨光致发光成像测量了MoSe$_2$/WSe$_2$范德华异质结构中的IX输运。 这些测量探测了IX云扩展的动力学并揭示了输运特性。 我们发现IX输运具有异常高的扩散率，比范德华异质结构中常规扩散激子输运高几个数量级。 这种高效的IX输运与长程弹道输运一致，并与莫尔超晶格中超流体的玻色-哈伯德理论预测相符。 显示英文摘要

摘要： Exciton transport is fundamental for understanding transport phenomena in bosonic systems and for embracing excitation energy transfer in materials. Spatially indirect excitons (IXs) are composed of electrons and holes in separated layers. Long IX lifetimes allow them to form quantum bosonic states and travel long distances. In this work, we measured IX transport in a MoSe$_2$/WSe$_2$ van der Waals heterostructure by time-resolved photoluminescence imaging. These measurements probe the kinetics of IX cloud expansion and reveal the transport characteristics. We found IX transport with anomalously high diffusivity, orders of magnitude higher than for regular diffusive exciton transport in van der Waals heterostructures. This efficient IX transport agrees with long-range ballistic transport and is consistent with the Bose-Hubbard theory prediction of superfluid in moire superlattices.