A NOVEL PHASE-MATCHING TECHNIQUE FOR A POLED POLYMER WAVE-GUIDE

An electric field induced dynamic phase-matching which can improve the thickness tolerance of waveguide SHG device is first demonstrated usi ng organic nonlinear optical (NLO) materials with low glass transition temperature (Tg). The advantage of this technique is the possibility to control an effective refractive index of NLO waveguide at room temp erature. As a result of refractive index variation induced by an exter nal electric field, the effective phase-matching dimension can be cont rolled from 1.272 mu m to 1.260 mu m. The phase-matching condition i.e . conversion efficiency of second harmonic light can be easily tuned b y changing a poling electric field. The obtained net conversion effici ency of low Tg NLO slab waveguide was found to be 1.5 %. No decay of c onversion efficiency for low Tg NLO waveguide is observed in the prese nce of an electric field.