Polymer laser based on active waveguide grating structures.

The active waveguide grating structures (AWGS) are demonstrated as distributed feedback (DFB) configuration for polymer lasers. The thin film of a typical light-emitting polymer poly [(9,9-dioctylfluorenyl-2,7-diyl)-alt-co-(1,4-benzo-{2,1',3}-thiadiazole)] acts both as the gain medium and as the waveguide. The grating structures are fabricated separately on top of the polymer film through interference lithography. The continuous and high-quality waveguide layer of the gain medium enables laser emission with narrow linewidth. Theoretical analysis and experimental verification imply potentially excellent performance of the organic DFB lasers based on the AWGS configuration. This kind of AWGS configuration is of particular importance for the design of electrically pumped polymer lasers.