Publication date: 22nd July 2026
Two-dimensional hybrid perovskites are a highly intriguing class of materials, composed of alternating inorganic and organic molecular layers. Their reduced dimensionality combined with weak dielectric screening leads to the formation of tightly bound excitons that efficiently absorb and emit radiation. A central questions for excitons in perovskites from the perspectives of both fundamental physics and applications is their mobility. In addition, the flexibility of the material design allows for the integration of a variety of functional compounds including chiral molecules to enable polarization control of the optical response. Most importantly, the recently demonstrated presence of the exciton fine structure and the predictions of the associated non-equilibrium pose major questions regarding the energy transport in 2D perovskites mediated by excitonic carriers. In this talk I will focus on the transport of optically detected excitons in 2D perovskites via transient, ultrafast microscopy, featuring different regimes of propagation featuring free and localized states. I will demonstrate the strong impact of the exciton fine structure leading to extremely rapid propagation of hot excitons in 2D perovskites, discuss the impact of temperature and the associated transition to the equilibrated regime. This opens up interesting opportunities to design the exciton band structures with the possibilities to create scenarios enabling hot exciton extraction.
