Singlet Exciton Migration in a Conjugated Polymer by Picosecond Time-Resolved Photoluminescence

The transient photoluminescence (PL) of DO-PPV (poly-(2,5-dioctyloxy-1,4-phenylene vinylene)) solution in chloroform was
investigated by picosecond time-resolved PL spectroscopy. An ultrafast rise of PL and the following single exponential decay with a time constant about 400ps were assigned to the formation of intrachain exciton and its decay process, respectively. The redshift of the PL emission spectrum with time was caused by the subsequent exciton migration among the different conjugated segments in the DO-PPV polymer.