Effect of titania content on the optical properties of dye-doped hybrid sol–gel coatings

摘要: Abstract Sol–gel waveguides have been realized using a mixture of zirconium and titanium alkoxides with 3-Glycidoxypropyltrimethoxysilane (Glymo) as organic modifier. The molar ratio metal (Ti,Zr)/Glymo was 70/30 in order to obtain material high refractive index. Coumarin30 dye added into the matrix during synthesis concentration 2 × 10 −2  M. Optical properties investigated by spectroscopic ellipsometry UV–visible absorption measurements. Crack free 600 nm thick coatings were obtained index range 1.56–1.66, increasing Ti-content. Steady-state time-resolved fluorescence measurements evidenced an almost linear decrease efficiency Ti-content increases. Such behaviour can be related excited state quenching mechanism. (Zr 0.5 –Ti ) 70 /Glymo 30 coating could considered fair trade-off between waveguiding performance ( n  = 1.61; 3.2 dB/cm) efficiency.