Long-range ballistic transport of indirect excitons in a van der Waals heterostructure
Zhiwen Zhou, W. J. Brunner, E. A. Szwed, H. Henstridge, L. H. Fowler-Gerace, L. V. Butov
公開日: 2025/7/6
Abstract
Exciton transport is fundamental for understanding transport phenomena in bosonic systems and for exploring 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 kinetics in a MoSe$_2$/WSe$_2$ van der Waals heterostructure by time-resolved imaging of IX cloud expansion. We found efficient IX transport. Describing this transport as diffusive gives anomalously high diffusivity, orders of magnitude higher than for regular diffusive exciton transport in van der Waals heterostructures. The IX transport kinetics shows that this efficient IX transport is long-range ballistic transport.