Study of third-order optical non-linearity and electrical conductivity of sol-gel processed silica: poly(2-bromo-5-methoxy-p-phenylene vinylene) composite

A novel sol-gel processed silica: poly(2-bromo-5-methoxy-p-phenylene vinylene) silica composite was prepared using a soluble precursor. The optical properties of this material have been investigated using u.v.-visible and FTi.r. spectroscopy. The densification process was monitored by d.s.c. and t.g.a. The third-order non-linear susceptibility χ⁽³⁾ has been investigated for both the pure polymer and its sol-gel composite at 602 nm using femtosecond degenerate four-wave mixing. A relatively large χ⁽³⁾ value with a subpicosecond response is observed. The electrical conductivities of AsF₅ doped polymer and composite films were studied using four-probe measurement.