Femtosecond two-step carrier generation in conjugated polymers

Summary form only given. Conjugated polymers are currently being commercialized for applications in organic light emitting diodes. This class of materials also bears a large potential for applications in large-area photodetectors and solar cells. In such devices the underlying process is the field-assisted charge carrier generation. This process is currently a subject of intense experimental and theoretical investigations. From a fundamental point of view, charge carrier generation depends on the energetics and dynamics of intermediate states during the transition from a neutral photoexcited state (S/sub 1/-exciton) to a pair of free charge carriers. In our work we use a femtosecond two pulse excitation scheme and monitor the charge generation directly by detecting the photocurrent.