Silicophosphate films doped with organic compounds for nonlinear optical applications.

Doped organic compounds are of great interest for optical communications and high-density optical data storage due to their large second-order nonlinearity and high-speed response. A promising approach in the fabrication of new materials for second-order nonlinear optics is sol-gel technique. The present paper reports on the sol-gel synthesis of some pyrazolone derivative doped SiO-PO films. The precursors used for sol gel synthesis were tetraethylorthosilicate and phosphoric acid (HPO). The organic compound was added under continuous stirring in the precursors' mixture. The structure of the deposited azo-derivatives doped thin films was examined by Fourier transform infrared spectroscopy, and atomic force microscopy and their optical properties by UV-VIS spectroscopy. The nonlinear optical efficiencies due to the interaction of the NLO-active chromophores with the inorganic matrix has a significant influence on the second harmonic generation capabilities that was measured using a femtosecond Ti:sapphire laser. The properties of the films were investigated and correlated with the concentration of the organic dopant and the thermal treatment temperature. [ABSTRACT FROM AUTHOR]