A soluble poly(2-methoxy-5-decoxy)-p-phenylene vinylene (PMODOPV) was synthesized via dehydrochlorination reaction and characterized by UV-visible absorption spectrum. The results showed that PMODOPV had a broad optical absorption band in the range of 450---550 nm and the optical band gap was calculated to be around 2.12 eV. The third-order nonlinear optical susceptibilities (χ(3)) of PMODOPV films implanted by 30-keV N+ ions in the dose range of 3.8 * 10^(15)---9.6 * 10^(16) ions/cm2 were measured by degenerate four-wave mixing (DFWM) technique. The results demonstrated that the resonant and off-resonant χ(3) values were all enhanced significantly by means of ion implantation. The maximum resonant χ(3) value of 9.67 * 10^(-9) esu at 532 nm and off-resonant χ(3) value of 2.49 * 10^(-10) esu at 1.064 μm were obtained when the ion dose was 3.8 * 10^(16) ions/cm2.

A tunable Fabry-Perot (F-P) filter by using electro-optic polymer film is proposed. The electro-optic polymer is alkoxysilane dye (ASD)/SiO2-TiO2 hybrid material, whose electro-optic coefficient γ_(33) is about 5 pm/V. The wavelength tuning range of 3.8 nm under 400-V DC voltage and the nonlinear characteristic with the electric field have been obtained via electro-optical properties of polymer. Both of polymer film fabrication and F-P filter designhave been introduced. The tunable F-P filter is designed for the application of two-input/two-output port wavelength-selective optical switch. Also, some problems have been discussed in this letter.

Most alternating current (ac) polymer EL (electroluminescent) devices to date are based on symmetrical structure. Here novel alternating current EL devices with asymmetric structure are successfully fabricated by using a hole type polymer PDDOPV [poly (2,5-bis (dodecyloxy)-phenylenevinylene)] and an electron type polymer PPQ [poly (phenyl quinoxaline)]. We report that performance of polymer devices with heterojunction in ac operation is not so sensitive to thickness of the two polymer layers as in direct current (dc) operation. This new advantage of ac operation mode over dc means easy production and cheap facilities in large-scale production in the near future. Different emission spectra are obtained when our ac devices operate in ac mode, forward and reverse bias. Emission spectrum at reverse bias includes two parts: one is from PDDOPV, the other is from PPQ.