Ultrafast terahertz snapshots of excitonic Rydberg states and electronic coherence in an organometal halide perovskite.

ABSTRACT: How photoexcitations evolve into Coulomb-bound electron and hole pairs, called excitons, and unbound charge carriers is a key cross-cutting issue in photovoltaics and optoelectronics. Until now, the initial quantum dynamics following photoexcitation remains elusive in the hybrid perovskite system. Here we reveal excitonic Rydberg states with distinct formation pathways by observing the multiple resonant, internal quantum transitions using ultrafast terahertz quasi-particle transport. Nonequilibrium emergent states evolve with a complex co-existence of excitons, carriers and phonons, where a delayed buildup of excitons under on- and off-resonant pumping conditions allows us to distinguish between the loss of electronic coherence and hot state cooling processes. The nearly ∼1 ps dephasing ti

SUBMITTER: Luo L 

PROVIDER: S-EPMC5461501 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature