Sol-Gel Processed Conjugated Polymers for Optical Waveguides

Novel sol-gel processed poly(1,4-phenylene vinylene) (PPV) and poly(2,5-disubstituted-1,4-phenylene vinylene)/silica composites were prepared by a soluble precursor technique. The two PPV derivatives included in this study were poly(2-bromo-5-methoxy-1,4-phenylene vinylene) and poly(2-butoxy-5-methoxy-1,4-phenylene vinylene). The spectral characteristics of these materials have been investigated using UV-visible and FT-IR spectroscopy. The densification process was studied by differential scanning calorimetry and thermal gravimetric analyzer. The third-order nonlinear susceptibility χ⁽³⁾ have been investigated for the polymers themselves and their sol-gel composites at 602nm using degenerate four-wave mixing (DFWM) technique. Relatively large χ⁽³⁾ values (4 × 10⁻¹⁰ ∼ 1 × 10⁻⁹ esu) with a subpicosecond response were observed.