Speaker: Douglas Garratt, Imperial College
Program Description:
In this talk I will present our work in applying time resolved x-ray absorption spectroscopy (TRXAS) to organic semiconductors. These materials have attracted significant research interest both due to their rich photochemistry and their application in low cost, flexible solar cells. TRXAS has the potential to provide a unique insight into charge photogeneration and transfer in these systems due to its sensitivity to charge localisation. We use an attosecond soft x-ray supercontinuum generated via high harmonic generation to measure x-ray absorption spectra of poly(3-hexylthiophene) (P3HT) at the sulfur L and carbon K edges. This is combined with a ~15 fs optical pump pulse to track the dynamics following photoexcitation of the p - p* transition, relevant to solar energy conversion.
