Solid state organic laser emission at 970nm from dye-doped fluorinated-polyimide planar waveguides

We have demonstrated near-infrared amplified spontaneous emission and laser emission from fluorinated-polyimide waveguides doped with an organic dye, 5,6-dichloro-2[8-(p-dimethylaminophenyl)-2,4-neopentylene-1,3,5,7-octatetraenyl]-3-ethylbenzothiazolium perchlorate (LDS950). The planar waveguides doped with 1wt% of the dye, 10mm in length and 9.3μm in thickness, have exhibited amplified spontaneous emission and optical gain around 960nm under optical pulse pumping. A good optical gain coefficient of 1.4mm−1 was obtained. Furthermore, by using the cleaved waveguide edges as reflective facets, sharp emission peaks showing laser oscillation at 970nm were observed under the optical pulse pumping. The lasing threshold was 0.22mJ∕cm2. The lasing wavelength of 970nm is the longest for solid state dye-doped polymeric lasers.