Recombination of electronic excitations in regioregular poly(3-hexylthiophene)

We use optical spectroscopy to study the recombination dynamics of long-lived polarons in thin films of regioregular poly(3-hexylthiophene) (RRPHT). The modulation-frequency dependence and transient decay of the photoinduced polarons in RRPHT has been measured and modeled using a bimolecular recombination mechanism. In both cases, the data can be explained with two relaxation times, a slow component in the ms time regime and a faster component in the μs time regime.