We present a transient absorption spectroscopy study of oriented poly(9,9-dioctylfluorene) film. By comparing the spectral features and dynamics at different wavelengths using different probe polarizations, we conclude that three species are generated after the photoexcitation: hot carriers, excitons, and charged polarons. The charged polaron spectrum is measured with the probe beam polarized perpendicular to the polymer chains, and two bands are recognized. In addition, a new band in mid-IR regime is observed that decays faster than excitons, and whose peak shifts in time. This feature is assigned to hot carriers.
|Number of pages||4|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - Nov 15 2001|
ASJC Scopus subject areas
- Condensed Matter Physics