Abstract: Tellurium-based composite films with third-order nonlinear optical properties were prepared by electrochemically induced s S ol-g G el method using ITO glass as the substrate. The surface morphology and composition of the thin films were characterized by SEM (scanning electronmicroscopy e ) and EDX (X-rayenergy- dispersion spectroscope ). The transmission spectrum, reflectance optical spectrum and absorption spectrum of the thin films were recorded on a spectrophotometer and the third-order optical nonlinearity of the films were measuredby Z-scan technique with pulsed laser.SEM revealed a network structure of the films and EDX measurement identified Si, Te and O elements as the main components. Negative effectnonlinear refraction and saturated absorption properties were observed at the wavelength of 1064nm with a nonlinear refractive index of - 4.18?10 ^{- 13} m²/Wand nonlinear absorption coefficient of the - 1.6?10 ^{- 6} m/W, respectively,showing obvious nonlinear optical properties. The third-order nonlinear optical susceptibility was found to be 1.13?10 ^{- 14} (m/V)²,demonstrating that third-order nonlinear optical properties of the films wereexcellent.

Key words: Tellurium-basedcomposite materials, Thin films, Z-scan technology, third-order opticalnonlinearities