Ultrafast optical response in polydiacetylenes and polythiophense was investigated by femtosecond time-resolved absorption spectroscopy. Several nonlinear optical processes, i.e. hole burning, Raman gain, and induced-frequency shift, were observed and the third-order nonlinear susceptibilities were determined. The ultrafast relaxation dynamics following after the photoexcitation was investigated and the formation and relaxation of self-trapped exciton was observed. A model of the relaxation processes of excitons in conjugated polymers is proposed. The short life of STE and difference between fluorescent and nonfluorescent polymers are explained.
|Number of pages||6|
|Journal||Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals|
|Publication status||Published - 1992 Jun 1|
ASJC Scopus subject areas
- Condensed Matter Physics