Femtosecond Transient Absorption Microscopy of Singlet Exciton Motion in Side-Chain Engineered Perylene-Diimide Thin Films.

ABSTRACT: We present a statistical analysis of femtosecond transient absorption microscopy applied to four different organic semiconductor thin films based on perylene-diimide (PDI). By achieving a temporal resolution of 12 fs with simultaneous sub-10 nm spatial precision, we directly probe the underlying exciton transport characteristics within 3 ps after photoexcitation free of model assumptions. Our study reveals sub-picosecond coherent exciton transport (12-45 cm² s^-1) followed by a diffusive phase of exciton transport (3-17 cm² s^-1). A comparison between the different films suggests that the exciton transport in the studied materials is intricately linked to their nanoscale morphology, with PDI films that form large crystalline domains exhibiting the

SUBMITTER: Pandya R 

PROVIDER: S-EPMC7132576 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature