Picosecond gain switching of an organic semiconductor optical amplifier

All-optical switching of an individual pulse within a sequence of amplified pulses is demonstrated in a conjugated polymer optical amplifier. The switching was achieved using a control pulse resonant with the excited state absorption. An extinction ratio of similar to 5.5 dB was observed, while the intensities of the remaining pulses in the sequence, spaced at 50 ps intervals, were unaffected. A pump-probe study was performed and showed full gain recovery within 2 ps. (c) 2008 American Institute of Physics.