Femtosecond laser fabrication of microfluidic channels for organic photonic devices

We report on innovative application of microchannels with access holes fabricated by femtosecond laser irradiation followed by chemical etching. This technique allows us to demonstrate a novel approach to the achievement of organic photonic devices in which the properties of a conjugated polymer in solution are exploited in a microfluidic configuration to produce an easy-to-integrate photonic device. Filling the microchannel with a diluted polyfluorene solution, we exploit the unique properties of isolated polymeric chains such as ultrafast gain switching (switching response time of 150 fs) with a 100% on-off ratio. In addition, by dispersing nanoparticles in the polymeric solution we are able to achieve random lasing in the microchannel.