LIGHT AMPLIFICATION AND LASER-EMISSION IN CONJUGATED POLYMERS

We study optical gain and laser emission from semiconducting conjugate d polymers after strong optical excitation with femtosecond laser puls es. Stimulated emission from few-hundred-nanometer thin films results in a sharp increase in emission intensity and emission line narrowing. Very large optical gain due to the stimulated emission is measured di rectly by pump-probe spectroscopy. Using the large light amplification in these conjugated polymers, we demonstrated planar and ring lasers of very small sizes that are suitable for applications in integrated o ptics. Vertical cavity surface emitting lasers, distributed feedback t hrough surface relief grating, and whispering-gallery mode emission fr om ring resonators are demonstrated. (C) 1998 Society of Photo-Optical Instrumentation Engineers.