| In this thesis we report the nonlinear optical characterization of three novel Kerr media for ultrafast all-optical switching and laser technology applications. Using a tunable picosecond laser system and the Z-scan technique we measure, for the first time, the wavelength dependence (λ = 800–1600 nm) of the nonlinear refractive index and the nonlinear absorption coefficient of the conjugated polymers ADS111RE and CN-PPP and the laser crystal Yb:KGW. Similar measurements on a variety of reference materials, that include the silicate glass SF-59 and five common solvents, show a good agreement with the predictions of existing theoretical models and the few scattered experimental data available in the literature, thus verifying the accuracy of our experimental results. The principal conclusions, drawn by comparison with existing materials and figure of merit calculations, show that ADS111RE is an attractive material for all-optical signal processing at wavelengths larger than 1400 nm and that Yb:KGW is an excellent candidate for efficient Kerr lens mode-locking operation.; Furthermore, we present a refined evaluation of the theory and practise of Z-scan, and we demonstrate a method to fabricate polymer films of good optical quality and thickness up to few millimeters, that is particularly useful for Z-scan experiments. |
