Third-order optical nonlinearity studies ofp-heptaphenyl derivatives-doped sol-gel processed composite glass and THF solution by degenerate four-wave mixing and optical Kerr gate measurements

Abstract

We have investigated the nonlinear optical performance of new UV photostable dyes, didecyl and didecyloxy substitutedpara-polyphenyl heptamers (DDPPH and DDOPPH hereafter, respectively) using the techniques of degenerate four-wave mixing (DFWM) and optical Kerr gate (OKG). The studies were performed on the dyes dissolved in THF solution and doped in sol-gel processed composite-glass. The magnitudes and the signs of the real and the imaginary components of the complex third-order optical susceptibilities were determined by the heterodyned OKG method and compared to the values obtained from concentration dependent homodyne Kerr gate and DFWM measurements. The observed effective second hyperpolarizability γ values are dependent on the optical intensity and the pulse width of the pumping source beam. Doping of the dyes in composite-glass allows to increase the interaction length providing the prospect of using them as building blocks for photonic devices.