SYNTHESIS OF FREQUENCY-DOUBLING NONLINEAR-OPTICAL POLYMERS, FUNCTIONALIZED WITH AMINONITRO STILBENE DYES - 2ND-HARMONIC GENERATION IN CORONA POLED THIN-FILMS

The synthesis and second harmonic coefficients, d33, and d31 as well a s the related susceptibilities, chi(zzz)(2), of two new series of (NLO -dye methacrylate)-(methyl methacrylate) copolymers were investigated. The NLO-chromophores bound covalently to the polymer chain were 4-nit ro-4'-dialkylamino-alpha-cyano-stilbene, 4-nitro-4'-dialkylamino-stilb ene. Thin films were obtained by spin-coating and poled by a positive corona discharge using a needle electrode in order to induce noncentro symmetry into the systems. Nonlinear susceptibilities, chi(zzz)(2), of the films were derived from the analysis of full-angle Maker fringe p atterns at 1064 nm. Chi(zzz)(2) values as high as 3.2 . 10(-7) esu cou ld be measured.