OPTICAL PREPARATION OF POLYMERS FOR PHASE-MATCHED FREQUENCY-DOUBLING

The nonlinear optical process which permits the optical preparation of centrosymmetric materials for frequency doubling is described in term s of an orientational hole-burning effect induced through non-zero E(3 ) resonant six-wave mixing. A permanent all-optical poling is achieved by seeding preparation under backward and forward geometries in an az oaromatic acrylic copolymer. The frequency doubling second order susce ptibility reaches 90 pm/V, as large as using the more classical corona poling technique. This offers a new molecular engeneering route to th e control and optimization of phase-matched oriented microstructures f or frequency conversion and also for electro-optic organic devices.