Author/Authors :
Lee، نويسنده , , Yu Hsien and Yabushita، نويسنده , , Atsushi and Hsu، نويسنده , , Chain Shu and Yang، نويسنده , , Sheng Hsiung and Iwakura، نويسنده , , Izumi and Luo، نويسنده , , Chih Wei and Wu، نويسنده , , Kaung Hsiung and Kobayashi، نويسنده , , Takayoshi، نويسنده ,
Abstract :
Ultrafast pump–probe spectroscopy of poly(3-hexylthiophene) (P3HT) films was performed using a 9-fs laser and a broadband lock-in detection system. The fast geometrical relaxation (GR) time was attributed to the transition from a free exciton (FE) to form a bound polaron pair (BPP), and the time constant was estimated to be τGR = 90 ± 2 fs. The relaxation time constant of BPP was determined as τBPP = 710 ± 40 fs. The measurement of pump-power dependence enabled us to distinguish the defect trapping process of BPPs from other parallel decay processes and to determine the defect concentration of a P3HT thin film.
