Free carrier photogeneration in polythiophene versus poly(phenylene vinylene) studied with THz spectroscopy
Using THz time domain spectroscopy, we investigate ultrafast photoconductivity in two conjugated polymers, derivatives of poly(phenylene vinylene) (MEH-PPV) and polythiophene (RR-P3HT), to investigate free charge carrier dynamics. We find that the ultrafast photo-conductivity due to free charges is larger in the RR-P3HT than in the MEH-PPV sample. These charges are long-lived, remaining mobile for several nanoseconds, in contrast to the picosecond decay of free charges in MEH-PPV. By comparing our measured conductivities to charge mobilities inferred from microwave absorption measurements, we make estimates for the free carrier quantum yields.
|Journal||Chem. Phys. Lett.|
Hendry, E, Koeberg, M, Schins, J. M, Siebbeles, L. D. A, & Bonn, M. (2006). Free carrier photogeneration in polythiophene versus poly(phenylene vinylene) studied with THz spectroscopy. Chem. Phys. Lett., 432, 441–445. doi:10.1016/j.cplett.2006.10.105