Wavelength shifting of optical pulses in a polydiacetylene waveguide

Wavelength shifting in a polydiacetylene-poly(3-BCMU)-planar waveguide was observed. The effect, of relevance in the manipulation of optical signals, was obtained through nearly-degenerate frequency mixing (NDFM). Starting from a pulse s at frequency ?-s$/, the generation of the frequency-shifted pulse f at ?-f$/ and the simultaneous amplification of s occurred at the expenses of the pump p according to the relation ?-p$/ + ?-p$/ = ?-s$/ + ?-f$/. The ratio of the energy pulse f at the output to s at the input was defined as the conversion efficiency ?.