Two-photon pumped upconverted lasing in dye doped polymer waveguides

The first measurements of two-photon pumped upconverted lasing in a waveguide is reported. Nonlinear dependence of the upconversion signal on the square of the input pump intensity and associated spectral narrowing was experimentally observed in dye-doped polymer waveguides. The pump wavelength was 736 nm and the center of the lasing spectrum was 570 nm. The spectra shows excitonlike features at 630 and 654 nm not seen in the absorption spectrum.