Preparation and third order nonlinear optical property of rhodamine-6G-doped SiO2-TiO2 sol-gel thin films

Abstract

Sol-gel dip coating method was adopted to prepare Rhodamine-6G doped SiO2-TiO2 thin films. Effects of MTMS/TEOS ratio on the crack of the thin films during drying stage were studied. The cracking was greatly decreased with the increase of MTMS/TEOS ratio. Crack free thin films were obtained for the samples with MTMS/TEOS greater than 0.75. The optical absorption and fluorescence spectra of the thin films were recorded. The refractive index increases linearly with the increase of TiO2 content (20, 40, 60 mol%). The third order nonlinear susceptibility of the Rhodamine-6G doped SiO2-TiO2 thin films is (chi) (3) approximately equals 10-9 esu measured by the generate four wave mixing technique.